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Active and abandoned mine sites can be an irresistible- - and sometimes deadly - - draw for outdoor enthusiasts, particularly children and young adults. Despite repeated warnings, posted signs, and fencing, tragedies involving accidents on active and abandoned mine property continue to make headlines, especially with the arrival of warmer weather and the summer months ahead. Over the last few years, there have been dozens of tragic incidents involving children and adults ventur­ing onto active and abandoned mine property. They include: A 16-year-old youth suffered fatal injuries after his all-terrain vehicle became airborne in an accident at a gravel mine near Albany, New York. A young boy was electrocuted when he contacted a high-voltage power line while sliding down a stockpile at a sand and gravel mine in Grand Island, Nebraska during its off-shift hours.

Jan 1, 1999

By F. L. Wideman

SPURRED by demands of a buoyant economy for mineral products, output from mines in the United States established a new record. Removal of waste material, necessary for the extraction of economic minerals, kept pace with mine production. Earth moving by these two activities exceeded 3 billion tons, an increase of 5 percent over that of 1963. Crude materials from which metal or nonmetal products were derived accounted for 75 percent of the total. The remainder, mostly worthless, was classified as waste. Changes in the minerals industry result from many causes. Technological trends and labor productivity are among several significant and interrelated indexes that assist in the analysis of the changes. Therefore, a. study of productivity is helpful in measuring technological growth in mining. Concepts of productivity tend to vary with the purpose for which the term is used; frequently, productivity is expressed in terms of units of output per unit of labor, such as tons of ore per man-hour or man-shift. Comparisons of levels of productivity for a group of products are usually made using composites of output. Data for all metal and nonmetal mines except gold, silver, mercury, platinum metals group, and sand and grave were used to compile the composite for determining productivity for 1960-64. Copper ore, iron ore, and phosphate rock are mined mainly by surface methods, but characteristics of the deposits and differences in processing the crude material affect production of the commodities. Therefore, productivity data for these selected segments of the minerals industry reflect the influence of physical conditions on the exploitation of them.

Jan 1, 1965

By Donna L. Anderson

This U.S. Bureau of Mines report discusses the status of a laser-based guidance system to provide position and heading feedback and closed-loop control of tramming maneuvers for a continuous mining machine. The system has been developed and tested at the Bureau, and is now being prepared for underground experiments. The system hardware includes laser scanners, a sensor communication network, and host computer hardware. The system software includes a position and heading computation module and a tram control module. The description of the software includes discussions of laser data acquisition, error compensation methods, position and heading determination, safety checking for continuous miner tramming, and closed-loop tram control. The accuracy of the laser scanner's data, the reliability of the lasers in a dusty environment, and the system's accuracy on tracking the position and heading of the continuous mining machine are shown in the results of experiments performed at the Bureau. Conclusions are stated based on these experimental results, and further work to improve the system performance and prepare for underground testing is discussed.

Jan 1, 1990

By Charles F. Weber

Premature blasts of charges of explosives have caused many deaths in anthracite mines, and the causes of many of the blasts were not determined satisfactorily. Investigators often found fairly high potential differences between such metallic objects as rails, pipes, conveyor lines, or sheet-iron chutes in the working place where an accident had occurred. At one mine where a premature blast occurred in a rock tunnel, one workman was killed and two others were injured, and several days later a potential difference large enough to explode an electric squib was detected between the compressed-air pipe and the track rail; the voltage fluctuated and appeared to change with the movement of a locomotive. At another mine, a. workman was killed when a primed cartridge that he was about to load in a blast hole exploded in his hand. During the investigation, a potential difference was found between the conveyor line and the sheet-iron chute. During a 5-year Period, 61 fatalities and 771 nonfatal injuries were caused by explosives accidents in anthracite mines, and one of the chief causes of these accidents was premature blasts.

Jan 1, 1950

A major hazard to workers in underground mines is fire and the resulting contaminated air. Fire reaches miners thousands of yards away with carbon monoxide gas and other toxic fumes. The same ventilation system that furnishes fresh air to miners can also be the vehicle to carry contaminated air to remote locations. To reduce these problems, the U.S. Department of the Interior's Bureau of Mines entered into Contract H0242016, "Mine Shaft Fire and Smoke Protection System," with FMC Corporation, Santa Clara, California, to evaluate mine shaft fire and smoke hazards and to develop and demonstrate a low-cost, reliable mine shaft fire and smoke protection system that would be applicable to a majority of metal and nonmetal mine shafts, including raises and winzes, especially in deep mines.

Jan 1, 2011

By T. Bieniawski

"INTRODUCTION The Congress theme ""Improvement of Mine Productivity and Overall Economics by Modern Technology"" is probably beat: addressed by the subtheme allocated to this Plenary Session. It is appropriate that .Theme 1 emphasizes the simple point that effective use of geotechnical information is the key to improving mine productivity. In essence, this means that: (1) geological and geomechanics, (rock mechanics) data must be collected in sufficient quantity and of high quality; (ii) data interpretation must be performed specifically for purposes of engineering design; (iii) innovative design approaches should be used to bring about Improvements in productivity and safety.While, each of these three aspects .may: seem obvious to any mining engineer it is a fact that the above sequence is seldom followed and as a result, mining engineering not infrequently lags, behind other branches of engineering when it comes to design creativity, efficiency and safety.. . After all, mining is still-one of the most hazardous occupations and we are gathered here to discuss, at the highest world professional forum, how to use more effectively the modern technology. This however, does not mean that mining engineers are less capable than other engineers or that their achievements are any lesser; far from it! Mining engineers are the cream of the engineering society on whose efforts depends the welfare of mankind. Moreover, they have produced minerals and coal evergrowing quantities against evergrowing difficulties. Yet, we must and can become even better because we are not making full use of the modern technology and rock mechanics knowledge already at our disposal, and. we are not being innovative enough to the full extent of .our capabilities."

Jan 1, 1989

By W. T. Benson

In May l942, the Bureau of Mines started exploring for manganese on the Black Poch manganese property, Esmeralda County, Nev., to determine possible reserves of manganese in the deposits. The work was done by the Bureau in cooperation with the Federal Geological Survey and comprised a study of the geology, mapping the area, and exploring by trenching, test pitting, and sampling. All ore bodies were examined and sampled, and the three most important areas were explored by trenching and test pitting. This report notes the location, ownership, and history of the deposits; explains the physical features of the district; mentions briefly mine workings and metallurgy; and describes the geology and ore bodies. The Bureau erected a temporary camp, repaired 5 miles of temporary road, constructed 1,000 feet of new road, dug 3,173 foot of trenches with a vertical crone section of 4 x 10 feet and 91 test pits with a cross section 3 x 6 feet, averaging about 6 feet deep, and cut 134 samples.

Jan 1, 1950

By Kevin Connor

The mineral industry continued to be an almost negligible contributor to the country's economy as the Government continued its 1979 ban on any mineral exploitation for export; a policy initiated at the end of 1979. A national program had been underway since that time to map and inventory all mineral resources so as to permit future exploitation of mineral wealth in the beat interests of the country and its inhabitants. In March 1982, the British Sulphur Corp. Ltd., under contract to the Burundi Government and the International Bank for Reconstruction and Development (World Bank), began a feasibility study of Burundi's phosphate deposits at Matongo-Bandaga for potential commercial exploitation. The 1-year project effort was to define ore reserves, conceptually design mining operations and processing facilities, estimate capital and production cost, and develop a regional market and distribution survey. Work completed during the year comprised geological exploration and reconnaissance and 1,200 meters of core drilling. Reserves in excess of 5 million tons of ore-grade phosphate were estimated available for mining. Rare earth mineralization was associated with the primary apatite. The associated carbonatite within the rock matrix was preliminarily assessed to be of value as a raw material for the manufacture of cement. The contract effort was valued at $1.2 million? Matongo-Bandaga is located approximately 40 kilometers north of the capital city of Bujumbura and alongside one of the country's few paved roads.

Jan 1, 1984

By Lisa Steiner, Robin Burgess-Limerick

Working with or near underground coal mining equipment is hazardous because of the multiple sources of energy and adverse environmental conditions. Of the 4169 injuries reported to Coal Services during the three years to June 2005,447 were associated with continuous miners, 232 with LHD (load-haul- dump) vehicles, 140 with shuttle cars, and 140 with personnel transport - a total of 959, or 23% of all injuries reported during the period. An analysis of the injury narratives accompanying these injury claims highlights a number of opportunities for controlling injury risks. Using the frequency of reported injuries for the prioritisation of risk control strategies has limitations because of the tendency to underestimate the importance of relatively uncommon but potentially high consequence events. Injury reports also underestimate the contribution of risk factors such as whole body vibration, which have a long-term cumulative contribution to an elevated risk of injury. However, taking these limitations into consideration, the results of the injury narrative analysis suggests the following hazards as the highest priority for elimination or control: • handling continuous miner cable • strain while bolting • slipping off continuous miner platform • inadvertent or incorrect operation of bolting controls, and operation of controls while a person is in a position of danger • hitting potholes or other roadway abnormality • collisions while driving underground vehicles

By J. Davitt McAteer

Dear Mine Operator, Training for new employees, refresher training for new employees, refresher training, and new task training can mean the difference between life and death for workers. Part 46 spells out how you can develop a training program to protect workers for on-the-job hazards. Together, labor, industry, and the U.S. Department of Labor reached a milestone with the development and publication of Part 46. We want to continue working together toward the next milestone, October 2000, when the regulations take effect. We want to make sure you have all the information you need about these new training requirements. Throughout the next 12 months, MSHA personnel will be holding regional meetings across the country, delivering information and sample training plans to your operation, and offering you help to develop your plan. If you are among the many operators who are already providing training to your workers, keep up the good work. The rule will tell you exactly what is expected. If you currently have no training program, we can help you develop one. A brochure is being distributed, which highlights the main provisions of the rule. It is designed to introduce the rule to you. More detailed materials will be delivered to you. If you want information right away, simply call us, or e-mail us. We also welcome your comments, suggestions, and success stories. Part 46 will be successful and beneficial to miners through our combined efforts. Together, we can make our mines safe and healthier for everyone. Sincerely, J. Davitt McAteer, Assistant Secretary of Labor Mine Safety and Health Administration

Jan 1, 1999

By L. J. Froisland

The Bureau of Mines conducted a 4-year research program at Uravan, Colo., on a 2-1/2-acre reclamation plot on the slope of a uranium tailings pile that had been covered with mine waste rock. The purpose of this study was to determine the effects of plant species, type of irrigation, type of fertilizers, and use of dust control chemicals on plant growth and surface coverage. Best grass coverage, nearly 100 percent with 240 plants per square foot, was developed in a section that was seeded with crested wheatgrass, fertilized with sewage sludge, and sprinkler irrigated. For comparison, a section that had been treated with commercial fertilizers developed 3.1 crested wheatgrass plants per square foot and 24 percent coverage without irrigation, and 8 plants per square foot and 75 percent coverage with irrigation. Results of spraying a dust control chemical were inconclusive. Russian-thistle invaded all test sections and ranged in density from 0.6 to 7.3 plants per square foot.

Jan 1, 1982

By William H. Pomroy, Shail J. Butani

"This Bureau of Mines publication presents a statistical analysis of official U.S. Mine Safety and Health Administration (MSHA) metal and nonmetal mine fire reports from 1950 through 1984, plus accounts of selected nonreportable fires (less than 30 min and no injury) and opinion data on fire hazards from mine safety directors. Fires were analyzed by time trends, ore type, ignition source, burning substance, location in mine, equipment involved, means of detection, duration, number of injuries and fatalities, mining method, and successful extinguishing agent. The leading ignition sources were electricity in underground fires and engine heat in reported surface fires. The most frequent burning substance was combustible liquids for all nonreportable fires, reported surface fires, and reported underground fires from 1978 to 1984. For underground fires reported prior to 1978, timber was the leading burning substance. Mobile equipment was the type most frequently involved in both underground and surface fires. Underground fires occurred most often in haulageway or drift areas, and reported surface fires occurred most often in plant and mill buildings, while most nonreportable surface fires occurred in other areas. The most common methods of extinguishment were water hose lines for reported fires and dry chemical handportable extinguishers for nonreportable fires. INTRODUCTIONIn support of the Bureau of Mines research on mine fire protection, two separate baseline studies on mine fire incidents have been prepared. The first study addressed coal mine fires. The results of that study are summarized in the Bureau's Information Circular 8830, ""A Statistical Analysis of Coal Mine Fire Incidents in the United States From 1950 to 1977."" This second report, addressing metal and nonmetal mine fires, is the companion to IC 8830. Together, these two reports provide a comprehensive, factual summary of the mining industry's fire experience.This report, like IC 8830, covers (1) MSHA fire incident reports, (2) records of nonreportable fires (less than 30 min and no injury), and (3) mine safety directors' opinions on fire hazards. The MSHA fire reports provide the most reliable, objective, and accurate historcial record of the major noncoal mine fires that occurred during the study period (1950 through 1984). However, MSHA fire reports alone understate the true magnitude of the fire problem because metal and nonmetal mines have been legally required to report fires to MSHA only since 1968. Although some fires were reported prior to 1968, doubtless a great many were not. Also, the reporting regulations that took effect in 1968 specify that only fires lasting 30 min or longer or involving an injury need to be reported. MSHA fire reports are thus limited in scope by MSHA's legal authority. In order to provide a more comprehensive data base, it was also necessary to gather and analyze mine company records of nonreportable fires."

Jan 1, 1986

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 D. G. Kuehn

Studies were conducted by the Bureau of Mines to determine the positive ions and neutral species produced in glow discharges of gas streams containing 1.0 percent NO in helium, 29 percent dry air in helium, and 1.06 percent NO in N2, Mass spectrographic measurements were conducted for gas pressures from 2.3 to 10.0 torr and dc currents from 10 to 20 mAo Ion species observed included NO+, N2 +, O2 +, N+, and 0+ with lesser amounts of He+, He2+, and N02+. Variations in various ionic and neutral species with discharge duration were interpreted to be consistent with an electrically induced dissociation of NO to produce N2 and O2. No nitrogen oxides were observed to form in glow discharges of the helium-air mixture.

Jan 1, 1975

By Peter H. Toepfer

This report presents the factual data obtained by the Bureau of Mines during diamond-drilling investigation of the Sunset copper deposit in the Index mining district, Snohomish County, Wash. The Sunset mine, first produced copper ore in 1902, but its main period of activity was from 1923 through 1930, The mine has produced 263,500 tons of ore, from which 1,500 ounces of gold, 156,000 ounces of silver, and 12,912,000 bounds of copper-were recovered. The mine has, been idle since 1946

Jan 1, 1953

By Douglas A. Donato

This Information Circular presents the MULSIM/PC system of numerical modeling computer programs developed by the U.S. Bureau of Mines. This system consists of four programs: PREMUL, the preprocessor or mesh generator; MULSIM/PC, the actual numerical modeling program (number cruncher); MUL3D, a three-dimensional postprocessor; and MUL2D, a two-dimensional postprocessor. These programs were specifically designed to operate on IBM-compatible (MS-DOS-based) personal computers for easy transfer of this technology to the mining industry and academia. MULSIM/PC uses a subvariation of the boundary-element method, namely, the displacement-discontinuity technique, for linear-elastic geomechanical analysis of mine plans in one or two parallel underground tabular deposits. Results calculated by this technique include stresses and displacements as they relate to changing mine geometries and materials. In addition to describing the MULSIM/PC program and its features, and providing a detailed example model, this report also documents the associated preprocessing and postprocessing programs that are part of the MULSIM/PC system. User's guides for all the programs are contained in the appendixes following the main report.

Jan 1, 1992

By V. A. Marple, K. L. Rubow, B. A. Olson

"A virtual impactor personal aerosol sampler (VIPAS) bas been developed for use in diesel-equipped mines to collect size-separated samples or diesel exhaust and mine dust particles in the respirable size range. This sampler consists or three stages: a 10-mm cyclone, a 0.8- µm cutpoint virtual impactor and two filter cassettes. The large non-respirable particles are removed in a 10-mm cyclone. The respirable particles from the cyclone pass through a 0.8- µm cutpoint virtual impactor with the particles larger than and smaller than 0.8 JI.ID (mine dust and diesel exhaust particles, respectively) collected on two 37-mm filter cassettes. The sampling How rate is 2 L/min so as to be compatible with the standard respirable dust sampler and personal sampling pumps. INTRODUCTIONThe mining industry has been increasing its use of diesel-powered equipment in underground mines, especially in coal mines. With this increased usage has come an increased concern regarding the health effects associated with inhaling diesel exhaust particles since they are in the respirable particulate size range. A Mine Safety and Health Administration (MSHA) advisory committee directed MSHA to develop a sampling protocol for diesel exhaust particles to assess worker exposure (MSHA, 1988). In addition, the National Institute for Occupational Safety and Health (NIOSH) has recommended that ""whole diesel exhaust be regarded as a potential occupational carcinogen as defined in the Cancer Policy of Occupational Safety and Health Administration"" (NIOSH, 1988).Past work, with cascade impactors in both the laboratory and in underground coal mine studies, has shown that the diesel exhaust particles are primarily in the less than 0.8 µm aerodynamic diameter size range whereas the coal dust particles are primarily greater than 0.8 µm (Marple et al., 1986; Cantrell, 1987; Rubow and Marple, 1988; Rubow et al., 1990a, b; Cantrell and Rubow, 1991). This work has been jointly performed by the University of Minnesota and Bureau of Mines researchers over the last 8 years. Typical particle size distributions for a diesel-equipped coal mine and an all electric coal mine are shown in Figure l. Note that the particles in the < 0.8-µ.m mode are the diesel exhaust particles (seen only in diesel-powered mines) and the particles in the > 0.8-µ.m mode are coal particles (seen in both the electric-powered and diesel-powered coal mines). Chemical mass balance analysis was also performed on these two size fractions to determine the degree of particle cross-contamination in the two modes. This analysis showed less than 10% cross-contamination, i.e., in coal mines Jess than 10% of the diesel exhaust particulate was collected in the coarse fraction and Jess than 10% of the mine dust was collected in the fine fraction (Cantrell, 1987; Rubow et al., 1990a)."

Dec 1, 1996

By Robert S. Sanford

This paper deals with truck haulage methods and costs at one of the many open-cut mines that are replacing rail haulage with heavy-duty trucks. At this mine, ore is trucked to a crushing plant, centrally located within one of the open-cuts. The requirements for efficient low-cost truck haulage are: Good trucks designed for heavy loads, adequate truck maintenance, smooth roads, and well-trained truck drivers The weighted average cost of hauling a long ton of ore to the crusher and the waste to the dump was reduced from $0.1993 in 1948 to $0.1114 during the last half of 1949, his corresponds to a cost per ton mile of $0.0864.

Jan 1, 1952

By N. F. Le Jeuns

For a number of years the Bureau of Mines has conducted semi-annual surveys to determine the changes in motor gasoline being sold in the United States. It was pointed out in the previous survey that there was an apparent tendency toward greater uniformity in the character of gasoline marketed in the United States. This practically uniform tendency which continued from April, 1917 to January, 1923, has been interrupted in the, present survey, as shown by an examination of the column marked "Difference," as given in Table 1. The figures in this table were obtained by averaging the end points of the least volatile and most volatile samples of gasoline. For example, of 850 samples analyzed in 1919, the 10% ,(85 samples) having the highest end points and the 10% having the lowest end points mere grouped, and the end points of each group averaged. These averages are represented in the table as the "Maximum 10%" and the ?Minimum 10%? respectively. The same process was used on the other surveys.

Jan 1, 1923

By Edward D. Thimons

The Bureau of Mines conducted in-mine tests to determine correction factors applicable to low-velocity airflows (below 150 fpm) measured by the smoke cloud, vane anemometer, and oil of wintergreen tracer gas techniques 0 The average correction factors found for these methods of measurement were lower than those reported in the literature for use with higher velocity measurements. All tests measured airflows with controlled average velocities ranging from 50 to 100 fpm. Correction factors averaged about 0.75 for readings taken by the centerline smoke cloud method, remotely controlled and stickheld center" line anemometer, and split traverse stick-held anemometer. For hand-held centerline anemometer and oil of wintergreen tracer gas readings, correction factors averaged about 0.67. Since special anemometers are needed to measure airflows in this low-velocity range, and since proper calibration of these anemometers is difficult and expensive, the use of anemometers for low-velocity measurement is imprac-tical. On the other hand, smoke and oil of wintergreen give results as con-sistent as those obtained with specially calibrated, low-velocity anemometers. Furthermore, they are easy to use and inexpensive.

Jan 1, 1979