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By Mary E. Cocklan-Vendl

Regulatory processes associated with development of major mining operations in Alaska and British columbia were evaluated using specific case studies. Included were one hard rock mine in Alaska (Red Dog Mine), one hard rock mine In British Columbia (Snip Mine), and one offshore gold dredging project in Alaska (WestGold SIMA). Based on a comparison of the three case studies, it became clear that the primary incentives for cost effective permitting are: 1) early and continuing coordination of proposed project plans, designs and schedules with key regulatory agencies and local area residents and 2) development of a sufficient level of baseline information on air quality, water quality, wetlands, endangered species, fish and wildlife, and socia-cultural conditions to support the required permit application. The U.S. permitting process worked in much the same way as the Canadian permitting process. Disincentives of mine permitting include high initial costs for baseline data gathering. However, a relatively high early investment resulted in more efficient permit acquisition and reduced long-term monitoring requirements. A common problem Identified was the inadequate supply of trained agency personnel with the requisite technical and permitting experience. This sometimes resulted in poor decisions and unnecessary changes in project plans and schedules.

Jan 1, 1993

By Irving Hartmann, John Nagy

As part of a program designed to promote safety in industrial operations , the Bureau of Mines has been investigating the explosibility of numerous powdered products and dusts and studying means for the prevention of dust explosions . In a previous paper the results of a study of the inflammability and explosibility of metal powders were published . This report summarizes a similar study which has been made on various powders used in the plastics industry. The work was undertaken to provide information for a subcommittee of the Dust Explosion Hazards Committee of the National Fire Protection Association, which was charged with preparation of a code for the prevention of fires and dust explosions in plants producing or processing synthetic resins and molding compositions . The production of powders and generation of inflammable dusts are inherent in one or more steps of the manufacturing process of many resins and molding compositions, and control of the dust hazard is a major problem in the plastics industry . In the preparation of phenolic resin molding powders, for example , the solid synthetic resin is crushed and pulverized , and then blended with ground wood flour , cotton flock, or other fillers , as well as with coloring pigments . This raw mix is then passed through compounding mills , from which it emerges in the form of homogeneous sheeted stock, which is crushed , ground , and graded to form the molding powder . The number of major dust explosions in the plastics industry has been limited, but numerous small explosions have occurred, and in view of the ever -increasing volume of production the potential explosion hazard must be considered a very real one . Fortunately, this fact is realized by several manufacturers of plastic compounds , as well as by insurance companies , who are taking precautionary measures against possible accidents and during the past year or two have submitted numerous powder samples to the Bureau of Mines for explosibility tests .

May 1, 1944

By Liming Yuan, John C. Edwards, Gene F. Friel, Robert A. Franks

Diesel fuel fire experiments were conducted in NIOSH’s Pittsburgh Research Laboratory’s (PRL) Safety Research Coal Mine (SRCM) to determine the critical air velocity for preventing smoke rollback. Such information is necessary for the preplanning and implementation of ventilation changes during mine fire fighting and rescue operations. The fire intensity varied from 50 kW to 300 kW depending upon the fuel tray area. Airflow in the 2 m high and 2.9 m wide coal mine entry was regulated during the course of each experiment; measured upwind from the fire as an average over the entry cross-section with an ultrasonic airflow sensor; and recorded dynamically with a mine monitoring system. The extent of smoke reversal was monitored with light obscuration monitors, ionization smoke sensors, and visual observations. Experimental results for the critical air velocity for smoke reversal as a function of fire intensity compared very well with model predictions based upon a computational fluid dynamics (CFD) fire dynamics simulator.

By Warren M. Mahan

A rotary kiln process was developed by the Federal Bureau of Mines to produce consistently an iron product containing 3 to 7 percent nickel. Cuban laterite and serpentine ores were smelted in a gas-fired batch-rotary kiln) 5 feet in diameter and 9 feet long. The metal contained 2 to 4 percent carbon, with little or no silicon, and could be produced on a large scale with modest capital investment. A total of 121 tests was run using this procedure. The tests were conducted with a maximum temperature of 2,625° F., using linings of firebrick containing 40 to 70 percent alumina. Slags in the kiln were acid to neutral. The material in each batch passed through three stages: (1) Sponge metal, (2) carburization, and (3) balling and meltdown. Half the tests were made while firing the kiln with atmospheric-temperature air; the remainder were fired with preheated air. Tests showed that preheated air decreased fuel requirements, dust losses, and reducing agent, and increased the capacity of the kiln.

Jan 1, 1960

The Particulate Mineralogy Unit has been established at the College Park, Maryland, Metallurgy Research Center. The Particulate Mineralogy Unit will have the responsibility within the Bureau of Mines for the characterization of particulate minerals which have potential for adverse environmental effects. The Unit will provide a focal point for identifying particulates in connection with environmental problems related to the activities of agencies such as OSHA, HEW, EPA, and MESA. The Particulate Mineralogy Unit is seeking to clarify the ambiguities surrounding the mineralogy of and terminology used for asbestiform minerals and other mineral particles. The Unit?s investigations of the morphology, composition, and structure of asbestiform minerals and their nonasbestos analogs have made its members recognized experts in this field. The information which it develops on the characterization of asbestos and other particulate mineral forms such as silica should provide a technically rational basis for decisions by regulatory agencies. Those desiring further information, contact Dr. W. J. Campbell, Program Coordinator, College Park Metallurgy Research Center, College Park, MD 20740, telephone: 301-344-4014. ALUMINUM: For over a month, domestic producers have priced 99.5 percent grade primary aluminum ingot at 48¢ per pound. In the same period, merchants raised ingot quotes by 1.5¢-2.5¢ to a range approaching 44¢-47¢ per pound.

Jan 1, 1976

By W. T. Wertman

LABORATORY research has been started at the Bureau of Mines Morgantown Petroleum Research Laboratory, Morgantown, Va., to investigate the possibilities thermal-recovery methods for producing crude oils of high API gravity found in oil reservoirs of the eastern United States. This bibliography on thermal methods of oil recovery was compiled as a part of the work. Crude oil discoveries to December 31, 1958, in the United States were estimated to exceed 270 billion barrels. Cumulative production of crude oil through 19.55 was about 60 billion barrels, and the American Petroleum Institute estimates that an additional 30.5 billion barrels are economically recoverable by present methods. On this basis, about two-thirds of the oil that has already been found can be classified as economically unrecoverable for lack of a satisfactory method. The rap icily rising costs of proving new deposit; of domestic petroleum, the lack of new discoveries of large oilfields in the united States, and I he growing demand for crude oil have caused an acceleration of research to develop new or improved methods fur producing "unrecoverable" oil in known reservoirs.

Jan 1, 1960

By Robert M. Busche

[Recent developments in the gasification of coal, both by the Bureau of Mines and American industry, have intensified interest in the thermodynamic and kinetic principles necessary for understanding the reaction mechanism and rates and the physical changes that take place. In the course of a Bureau of Mines study of the kinetics of coal gasification at the Synthetic Liquid Fuels Demonstration Plant, Louisiana, Mo., a bibliography of approximately two references was compiled. They are listed n this publication and refer both to American and foreign sources.]

Jan 1, 1952

By George F. Dana

Oil yields, lithology, and stratigraphy have been evaluated for 15 cored wells and two sampled wells representing 10 square miles of the Tipton Member of the Green River Formation near Green River, Wyo. The area evaluated is being used by the Bureau of Mines for experimental production of oil from the oil shales in place. Lithology and oil yields were correlated to produce a stratigraphy diagram for the in situ study area, permitting precise designation of comparable sections. Because of lateral uniformity of oil shale, oil yields from eight cores and two sets of drill-cutting samples within a quarter section show the range of variation in average oil yield arising from experimental error. Variation in average oil yields from the seven cores representing the 10-square-mile study area lies within the expected experimental error. No difference in oil-shale richness across the study area is indicated. Average oil yields for three Tipton sections in the study area were deter-mined as follows: (1) The entire Tipton Member oil shale (about 145 feet thick), 13.3 gallons per ton; (2) the 40-foot upper rich zone, 21.0 gallons per ton; and (3) the 21-foot zone in which the Laramie Energy Research Center is conducting in situ experiments, 22.4 gallons per ton. One acre of the 21-foot experimental section represents 34,300 barrels of oil in place, and 1 acre of the Tipton's 40-foot rich upper layer represents 62,000 barrels.

Jan 1, 1972

By H. W. Earnest

This report covers the results of a two-phase study to determine the feasibility of underground disposal of retorted oil shale. Two mining methods, chamber and pillar mining and sublevel stoping, were specified for backfilling. Phase I of the study covered the evaluation of hydraulic, mechanical, and pneumatic transport and stowing systems, individually and in various combinations, and the selection of the most feasible methods. Conveyor transport and stowing and a combination conveyor transport and stowing with pneumatic topfilling were selected for detailed study of phase II. Phase II activities included detailed engineering analysis and design of the selected systems, an engineering economic analysis, and a cost comparison with total surface disposal of retorted oil shale. An extensive literature search was conducted and the bibliography is included in the report. Research done under Contract No. J0265052 by the Cleveland-Cliffs Iron Co. Available for reference at Bureau of Mines facilities in Denver, Colo., Twin Cities, Minn., Bruceton and Pittsburgh, Pa., and Spokane, Wash.; U.S. Department of Energy facilities in Carbondale, Ill., and Morgantown, W. Va.; National Mine Health and Safety Academy, Beckley, W. Va.; and National Library of Natural Resources, U.S. Department of the Interior, Washington, D.C. Order ONLY from NTIS:

Jan 1, 1978

By Anu Martikainen

Utilization of belt air in underground coal mines has been discussed extensively during the last decade. The Final Report of the Technical Study Panel on the Utilization of Belt Air and the Composition and Fire Retardant Properties of Belt Materials in Underground Coal Mining formed by the Miner Act of 2006 recommends research on leakage, use of booster fans, and escapeway safety. This paper discusses the role of ventilation modeling in evaluating primary escapeway pressurization in a three-entry development system to improve emergency escape in a coal mine using belt air. The intake entry of the NIOSH Bruceton Experimental Mine was pressurized using a 1.1 m (42 in) diameter, 37 kW (50 hp) fan. The work details air movement in the simulated three-entry system and the resulting leakage patterns. Three mine ventilation software packages were compared to analyze their performance in predicting the airflows and leakage conditions with different fan settings. NIOSH researchers found that the measurement results correlated well with the results of modeling.

Jan 1, 2010

By Elaine T. Cullen

Miners, like many skilled blue-collar workers, are not traditional learners. They have not always been successful in classroom-type settings, preferring to learn on the job in a hands-on environment. U.S. law requires that miners have a minimum of 8 hours of safety training annually, plus 40 hours for underground miners and 24 hours for surface miners when they enter the industry. However, miners rarely view this training time positively. In fact, it has been called “safety jail” by many, who regard it as a time to get a little extra sleep While mining has become far safer in the past 100 years, it is still a dangerous occupation. The Office for Mine Safety and Health Research, a part of the National Institute for Occupational Safety and Health (NIOSH), has funded a project for the past 4 years to address this challenge. The purpose of the research was to find a way to develop effective safety training for these people. Miners are born story tellers. They share “near miss” stories, stories about master miners they have known, and stories about how things used to be. These stories not only pass along information about what will happen if a miner fails to respect the mining environment, they also instruct listeners in the culture of mining and the values that it embraces. Stories, it seems, are a way to get safety messages across to miners, especially inexperienced ones, and using older, wiser miners in these stories is an obvious choice. This paper will discuss how a series of training videos was developed, how “master miners” and story lines were chosen, and how the resulting videos have been received in the mining industry.

By Michel C. Frippel

This section of the Minerals Yearbook reviews the minerals industries of 27 countries: the 12 nations of the European Community (Belgium, Dermark/Greenland, France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Portugal, Spain, and the United Kingdom); 6 of the 7 nations of the European Free Trade Association (Austria, Finland, Iceland, Norway, Switzerland, and Sweden); Malta; the 8 Eastern European economies in transition (Albania, Bulgaria, Czechoslovakia, Hungary, Poland, Romania, and Yugoslavia); and the U.S.S.R. Western Europe Western Europe [loosely defined to include the 12 nations of the European Community (EC) and the 7 nations of the European Free Trade Association (EFTA)] is the single largest trading area and consumer of raw materials in the world. If Western Europe was at one time an important mining sector, it has now increasingly relegated the role of supplying minerals for its minerals processing industry to the more minerally endowed countries in North and South America, Africa, and Australia. In this regard, Western Europe is the most important determinant of raw materials consumption (and thus, indirectly, raw materials production). Western Europe has significant reserves of industrial minerals but has limited availability of metalliferous raw materials. It, therefore, imports significant quantities of the latter and ranks along with the United States and the U.S.S.R. in the production of refined metals. Nonetheless, there is an inherent tendency to underestimate the importance of Western Europe in the world of minerals, both as a minerals processor and raw materials buyer. The reason for this is that Western Europe is generally thought of on the basis of individual nations rather than as a whole. Viewed in this limited context, the United States, the U.S.S.R., and Japan appear to dominate the world economy. Viewed as one regional area, however, Western Europe includes the fourth (FRG), fifth (France), sixth (United Kingdom) and seventh (Italy) largest economies of the world, all bordering on one another. With the remaining 15 EC and EFTA countries, Western Europe has a land area approximately 40 % of that of the United States, exceeds the U.S. population by 50 % and has a gross domestic product about the same as that of the United States.

Jan 1, 1993

By William C. Cooley

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Jan 1, 1975

By D. Harrington

"Coal—mine explosions are accidents that can and should be prevented. In former years hundreds of lives were lost each year in the United States as a result of such explosions, but after 1932 the numerous precautionary measures adopted had reduced their frequency and severity 75 percent or more until in 1940 several very disastrous explosions marred the good record. Unfortunately, both the number and severity of explosions seem to be tending to increase compared with the relatively good achievement from 1933 to 1940. The requisites for an explosion are ever present in all soft-coal and many hard-coal mines. A certain combination of circumstances, such as a flame or an arc in a cloud of dust or in a body of gas or both may start an explosion at any time. The fact that the frequency and severity of explosions were lowered for 6 or 7 years is no guarantee that such freedom from explosions will continue, as the bad record of 1940 has shown, and underground workers should feel honor bound to exercise the utmost care so that they will not help to bring about the circumstances that will cause an explosion.Although mine operators bear the main responsibility for preventing explosions, miners can do many things to help. As about 9 out of 10 explosions begin at a working face, it is largely within the power of workers to prevent them. All miners should do their part willingly and should not defend a fellow workman from punishment, even from discharge, for disobeying necessary rules, whose disregard may cause the death not only of the safety-rule breaker but also of many of his coworkers.When a miner is careless and is injured some other way than by an explosion he may be the only one to suffer, but if his carelessness causes an explosion he not only endangers his own life but also that of every other man in the mine and possibly the lives of persons outside the mine.Experiments have shown that ignition of as small a quantity as 150 cubic feet of an explosive mixture of methane and air under certain circumstances can start an explosion that will traverse an entire mine. Thus, ignition of an explosive mixture of gas 1 foot down from the roof and 13 feet back from the face of a 12-foot entry might cause a widespread explosion if the right quantity and kind of dust were present. Many persons have ignited much larger quantities of gas without being killed, but they survived only because dust, confinement, and other conditions were not exactly ""right."""

Nov 1, 1940

By John H. Johnson

This report covers the third and final year of work conducted under U. S. Bureau of Mines Grant G0166027, "Monitoring of Mine Air Pollutants". The report discusses work performed in three areas. These are the White Pine Mine (WPM) Experimental Unit, diesel mine-vehicle tailpipe emissions monitoring, and mine ambient air concentration data analysis. The WPM experimental unit was used to study diesel exhaust stratification in an 80 foot long dead-end heading while loading ore with a Wagner ST-5D scoop train LHD. The MTU Mine Air Monitoring Laboratory (MAML) was used to gather temperature and CO2 concentration data at 10 locations. Three different ventilation conditions were compared. The data substantiate the presence of strong buoyant forces of the hot exhaust gases which result in temperature stratification in dead-end headings. The diesel mine-vehicle tailpipe emissions monitoring study involved laboratory measurements of diesel undiluted exhaust pollutant concentrations by the portable tailpipe emissions measurement apparatus (EMA) assembled for in-mine use. The results were compared with simultaneous measurements by standard laboratory exhaust monitoring instruments. These results indicate that accurate field source quality control measurements can be obtained for CO2, CO and NO but NO2 results were low for all engine conditions. The mine ambient air concentration data analysis study included analysis of diesel pollutant concentration data in the Orchard Valley Mine air and comparison of the results with data collected earlier in the White Pine and Brushy Creek mines. The analysis included preparation of lognormal frequency distributions and calculations of C02-based concentration ratios and correlations. In the three mines compared, pollutant concentrations are distributed quite similarly, and the concentrations appear to be controlled to present standards.

Jan 1, 1979

By William C. Cooley

Data on equipment and components which have been used in hydraulic mining experiments, tests, and operations were collected from the literature. Also data were obtained from U.S. manufacturers and suppliers of equipment which is potentially applicable and available in the U.S. for hydraulic mining. The data have been divided into 24 main categories (see the following page) and have been assembled on two-page data sheets which follow. Wherever possible, drawings or photographs are included immediately after each data sheet.

Jan 1, 1975

By D. J. Dollhopf

An overburden handling dragline operation was conducted at a strip mine near Colstrip, Montana. The objective of the demonstration was to determine the degree a dragline could mix overburden inhibitory zones during the spoiling process. In order to quantify the mixing process the overburden was: 1) scatter spoiled; 2) dump spoiled; and 3) spoiled in a normal manner. This demonstration was part of an effort to investigate means of reestablishing non-polluted hydrological systems in areas where surface mining directly impacts shallow ground-water resources. When inhibitory material constituted < 5% of the total overburden volume, such material was essentially not detectable in the resultant spoil pile. When inhibitory material exceeded 15% of the overburden volume it was always found in the resultant spoil pile, generally with a smaller extent, indicating partial dilution. Inhibitory overburden zones often reappeared at the base or top of spoil piles in the potential aquifer and root zones suggesting the need for selective placement procedures. Scatter spoiling did not appear to be significantly more effective than normal spoiling, however clump spoiling seemed to produce less mixing of inimical zones. Mining activity has reduced ground-water levels within 1600 m of the active pit. The aquifer which is developing in spoils appears to have similar confinement characteristics as those that existed in the premined aquifer. To date no definite trends have been observed concerning changes in surface or ground-water chemistry associated with mining.

Jan 1, 1978

By Jeffrey A. Aldinger

This U.S. Bureau of Mines report presents an analysis of surface coal mining accidents involving mobile equipment for the years 1989 through 1991. Mobile equipment is defined as haulage trucks, front-end loaders, bulldozers, scrapers, and road graders. These five pieces of mining equipment accounted for 20 pct of all surface coal mine accidents and 41 pct of the fatalities. The general discussion of these accidents covers the accident causes, the primary activity of the accident victims, and other contributing factors. A more detailed analysis of accidents associated with each piece of mobile equipment is also provided. This report will provide mine managers and mine safety personnel with a better understanding of the hazards associated with mobile mining equipment. It identifies where improvements in mobile equipment safety can be made and those areas requiring additional safety emphasis, such as safety training, work procedure changes, or engineering changes to the equipment or work environment. The analysis was performed by a team of researchers using accident data and narratives provided by the Mine Safety and Health Administration.

Jan 1, 1995

By Robert T. MacMillan

A process has been developed in the laboratory and expanded to semi-pilot-plant scale for recovering titania, iron, and byproducts from two types of titaniferous iron ores. A reducing roast with coke and soda ash followed by grinding and magnetic separation produced powdered iron and slag from which titania and byproducts were recovered by H2SO4 decomposition. Based on the steps tested on a. semi-pilot-plant scale supplemented by the results of the laboratory investigations, enough data are available to make a balanced flow sheet. Combined data from the laboratory and semi-pilot plant indicated that 85 to 9O percent of the titania content of the ore was recoverable and that approximately 90 percent of the iron could be recovered as a metallic-iron powder. Tahawus magnetite from the Maclntyre mine at Tahawus, N. Y., was successfully treated as follows: (1) The ore was roasted at 1,050° to 1,080° C. with carbon and soda ash, thereby reducing the iron to metal sponge and retaining the titania in the slag. (2) The metallic iron was separated, after wet grinding, by magnetic or gravity means. (3) The slag fraction was air-roasted at 850° C. and leached with NaOH to recover Na3VO4. (4) The leached solids received a dilute-H2SO4 leach to remove interfering impurities, chiefly Na2O and SiO2. (5) Titania was dissolved from the leached solids of step (4) by a H2SO4-bake followed by a water leach. (6) Titania was precipitated by seeding and boiling the resulting solution. The spent liquor was used for the dilute-H2SO4 leach in step (4). The following scheme was found to be technically feasible for recovering other byproducts of the process. (1) The gelled filtrate from the dilute-acid leach step was washed and dehydrated to produce a commercially acceptable silica gel. (2) The wash liquor containing sulfates of Na2O, Al2O3, Fe2O3, and TiO2 was combined with the highly alkaline filtrate from the wet-grind and metallic iron-separation steps, precipitating iron and titanium hydroxides, which were separated for special treatment. (3) Anhydrous Na2SO4 and Al2O3?3H2O were recoverable from the alkaline filtrate from step (2) by evaporation and carbonation, respectively, and the barren liquor was recycled to the magnetic-separation step.

Jan 1, 1952

By Joseph J. Wallace, William H. Tavenner, D. A. Reynolds, John M. Provost, James J. Dowd, R. F. Abemethy

"CONCLUSIONSThe investigation shows that there are 5 coal beds of major importance in Wyoming County from the standpoint of present production - Pocahontas No. 3, No. 2 Gas, Sewell, Beckley, and Eagle - and 5 beds of minor importance - Pocahontas No. 6, Cedar Grove, Winifrede, Douglas, and Chilton. The Pocahontas No. 3 bed contains the largest remaining known reserves.Known measured and indicated reserves in all beds, based on a minimum thick¬ness of 14 inches and on 1,800 tons per acre-foot of coal in place, are estimated at 2,665 million short tons as of January 1, 1951. Of this total, 2,121 million short tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics are too meager to make an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.Recoverable reserves of coal have been estimated in beds 28 inches and more thick. This thickness is about the minimum now being mined by hand loading onto conveyors in the Appalachian region. The weighted average recovery for all beds in Wyoming County, as determined by this investigation, is 55.0 percent. This percent¬age is based on the total thickness of coal (less partings 3/8 inch or more thick) in the bed rather than on the thickness of the coal mined. The known recoverable reserves are estimated to be 1,167 million tons as of January 1, 1951.4. Since most of the Wyoming coals are medium- and low-volatile bituminous in rank and expand during carbonization in modern ovens, they are blended with high-volatile contracting coals."

Apr 1, 1953