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By Walter E. Pittman

In its role of providing technical assistance to the mining industry, the Bureau of Mines' Tuscaloosa Research Center has conducted research to develop trapped miner location systems which would aid in locating miners trapped by underground mining disasters. Efforts to produce electromagnetic systems for the location of trapped miners underground and to communicate with them were surveyed, from the 1920's to 1981. Theoretical studies of through-the-earth electromagnetic transmissions are described as well as studies of the electrical characteristics of various rocks, minerals, and soil. Several trapped miner location systems are reviewed including the Westinghouse systems, the DEVELCO system, and an automated three-dimensional location system, and the phase difference of arrival technique. Tangential research, relevant to trapped miner location systems is described. A comprehensive bibliography covering all aspects of trapped miner, through-the-earth electromagnetic location and communications systems is appended.

Jan 1, 1982

Research by the National Institute for Occupational Safety and Health (NIOSH) on multiple-seam mining has resulted in two new ground control products. Information Circular (IC) 9495 In some U.S. coalfields, particularly in central Appalachia and the West, most mines are operating above and/or beneath previously mined seams. The effects of multiple-seam interactions can include roof falls, rib spalling, and floor heave. These can seriously threaten the safety of miners and disrupt mining operations. Information Circular (IC) 9495 is a proceedings document containing a variety of papers that summarize recent knowledge about multiple-seam mining. A NIOSH study that analyzed case histories collected from 44 U.S. coal mines is described in detail. The study confirmed that overmining is much more difficult than undermining, and isolated remnant pillars cause more problems than gob-solid boundaries. The study's results were the basis for the Analysis of Multiple-Seam Stability (AMSS) software package. The proceedings also contain two papers describing the LaModel family of software. The original three-dimensional version of LaModel is essential for detailed analyses of complex multiple-seam scenarios. LaM2D implements a simplified, two-dimensional model suitable for quick approximations of the multiple-seam stresses and strains. Three papers in the proceedings focus on case histories. One describes the extensive multiple-seam experience at the Harris No. 1 Mine in West Virginia, a second contains examples of "extreme" multiple-seam mining from the central Appalachian coalfields, and a third describes interactions with regard to longwall mine experiences in Pennsylvania, West Virginia, and Utah. The final paper reports on a numerical modeling study that provided some insight into the mechanics of multiple-seam mining. [ ] AMSS Software Package NIOSH has developed a simple, user-friendly computer program called Analysis of Multiple-Seam Stability (AMSS). AMSS can help mine planners to evaluate each potential multiple-seam interaction and take steps to reduce the risk of ground control failure. AMSS begins by evaluating the pillar design. It first calculates the single-seam pillar stability factor (SF)

Jan 11, 2007

By Roy F. Waters

An inventory was made by the Bureau of Mines of wastes of mineral origin, water requirements, treatment of wastes, and water treatment practice of 163 industrial installations in the Lower Missouri River Basin. This is the second and concluding report on the survey, conducted in cooperation with the Missouri Basin Field Committee of the Department of the Interior as part of the Missouri Basin project. Principal industries covered by this second report are: Sand and gravel, coal, meat, ice, brewing, paint, petroleum, chemical, fabricated metals, and a number of industries having either no waterborne wastes, or none of mineral origin. Gravel, sand, and silt from 47 producers are the major wastes, totaling 6 million tons annually, Coal mine wastes in the form of slurried solids from washing crude coal are second in volume, totaling 100,000 tons per year. They contain an average of about 40 percent coal. Salt is the third largest waste, amounting to 28,000 tons per year, Next is calcium carbonate, most of which is formed in water treatments, Because of its high unit value, chromic acid is important, although the waste quantity is much smaller; cyanide wastes are also significant because large quantities of sodium hydroxide and chlorine are consumed in their treatments prior to disposal. The various industries discharging wastes use 38 billion gallons of water annually; the recirculation rate is 109 billion gallons per year. The plants discharging no waterborne mineral wastes use 2 billion gallons of water per year and recirculate more than 1 billion gallons. Sand and gravel plants use 13.5 billion gallons; petroleum refineries use 10 billion gallons in direct use and recirculate 82 billion gallons per year.

Jan 1, 1962

By J. G. Donaldson

Optimum conditions are given for chloridizing pyrite, marcasite, chalcopyrite, arsenopyrite, stibnite, and covellite with chlorine gas. The formation of metal chlorides is affected by the time and temperature of chloridizing, and by particle size of the sample. Chloridizing data also are given for chemically precipitated antimony (III) sulfide and copper (II) sulfide.

Jan 1, 1962

By Clarence O. Babcock

Model pillars of limestone, marble, sandstone, and granite with length-to-diameter (L/D) ratios of 3, 2, 1, 0.5, and 0.25 (0.286 for granite) were tested to failure in axial compression to determine to what extent an increase in end constraint increased compressive strength. Adjustable steel rings, mechanically tightened about the ends of test specimens to create a radial prestress of 3,000 or 5,000 psi prior to the application of axial load, increased end constraint more than was possible in previous tests using solid steel rings. (Solid rings, epoxy-bonded to the ends of dogbone specimens, increased compressive strength compared with that of straight specimens without ring constraint.) During the loading cycle, additional end constraint was produced by lateral expansion of the specimens against the rings. The effect of the end constraint was to increase the compressive strength 55 to 58 percent for the shorter pillars of dogbone shape compared with the compressive strength of straight pillars with the same L/D ratios without ring constraint. Most pillars with L/D ratios of less than 2 were made stronger by end constraint. Pillars with an L/D ratio of 3 did not benefit significantly from end constraint. When the results from compression testing of straight specimens of rock in the laboratory are used to design mine pillars in situ, the pillars will be larger than necessary if the horizontal compressive stress is several thousand pounds per square inch greater than that resulting from the weight of the overlying rock alone. The L/D ratio can be increased by a factor of 1.76 for ratios in the range 0.25 to 3 and still provide the same compressive strength. The safety factor applied with straight specimen test results should also be acceptable for use with constrained pillar test results.

Jan 1, 1969

By Robert M. Baker

This document details the method whereby Allen Corporation of America gathered and analyzed data and developed an annotated bibliography of metal and nonmetal mine fire reports (1950-1979). The primary objective of this program was to develop the annotated bibliography which included MSHA accident reports and periodicals. Two additional objectives were to gather data on non-reportable fires and to conduct statistical analyses on the data to delineate trends. Data was acquired from three major areas: periodicals, MSHA fire reports, and mine safety directors. Data was separated into reportable fires (at least ½ - hour duration or injury), non-reportable fires, and opinion data. The data was then analyzed by time trends, state, ore, ignition source, burning substance, location, equipment, detection, duration, injuries, fatalities, and successful extinguishing agent. The authors make a number of recommendations: (1) improved stationary electrical equipment design and fire protection, (2) improved design of mobile equipment to separate combustibles from ignition sources, (3) improved maintenance, (4) improved housekeeping, and (5) improved training. The document is divided into two volumes and an appendix. Volume I contains data acquisition procedures, data analysis procedures, and conclusions and recommendations. Volume II contains a chronological list of mine fires and fifteen indexes to assist the reader in locating fire incident report of interest. The Appendix contains the annotated bibliography of over 300 metal and nonmetal mine fire reports and journal articles and a list of non-reportable fires.

Jan 1, 1980

By Paul Hatmaker

Diatomite is the name now generally given to a mineral substance composed of the tiny , skeletal remains of diatoms , which are microscopic , flowerless , water plants related to the algae ... This residuum is essentially hydrous amorphous silica. Common names for diatomite are : Diatomaceous earth , tripolite , kieselguhr , and infusorial earth . Strictly speaking , however , the latter material is not diatomite , as it is composed of the fossil remains of infusoria , which usually do not occur with the diatomaceae . Other synonyms for diatomite are : Diatomaceous silica , kieselmehl , bergmehl , diatomeenpeelite , polirschiefer , moler , molera , molererde , de smid earth , fossil flour , mountain flour , farine fossil , white peat , radiolarian earth , chalk rock, ceyssatite , randanite , and tellurine ; also various diatomite products of individual companies are known by their own trade names . Diatomite should not be confused with fuller's earth , for the two are separate and distinct substances . Bentonite , pumice , and tripoli , have also been used erroneously to designate diatomite . Tripolite , however , is a true diatomite formerly mined near Tripoli ..

Feb 1, 1931

By Akul Joshi, Ming C. Leu, Robert Guttenberg, Susan L. Murray

The aerospace and automotive industries are facing a significant risk for cumulative trauma disorders from high-repetition, long-duration tasks. Additional risk factors such as shocks, vibrations and sustained uncomfortable postures oftentimes contribute to musculoskeletal, neurological injuries associated with the hand-arm system. The power tools used for the operation reduce the comfort and working efficiency of the operators, thus lowering their health and safety and the quality of operation. This paper investigates the fastening operation on the assembly line of a major aerospace company for quantifying hand-arm vibrations with the objective of developing a dynamic model of the hand-arm system. The model will be used to ascertain the effect of the various risk factors on the quality of the operation. Experiment Setup A system of three tri-axial accelerometers is used to collect vibrations entering the hand-arm system and their positioning follows the ISO-5349 standard. Reaction force during the operation is measured using a force sensor. The posture of the hand-arm system is measured using two goniometers and one torsiometer. The pilot study conducted has two subjects and one pistol-grip power tool. The experiment setup and positions of various sensors is depicted in Figure 1. [ ] Analysis Method The analysis consists of transmissibility of vibrations and frequency weighted acceleration based on the recommendations of the ISO-5349 standard [1,2]. The transmissibility [3] was deduced in frequency domain after measuring data in time domain from the

Jan 6, 2006

By J. A. Kosek

Work has been carried out under Bureau of Mines Contract No. HO395132 to develop and fabricate gas sensors for mining applications. Promising new instruments have been designed, developed, tested and supplied to meet BuMines requirements. These instruments include prototype 1) remote-sensing, diffusion-type CO monitors for mine operation which can be operated in conjunction with a surface computer, 2) control modules for alternate in-mine readout of the remote diffusion type CO monitors, 3) personal CO diffusion-type dosimeters and 4) personal NO diffusion-type dosimeters. In addition, retrofit modifications were made to update and optimize operation of CO and NO2 direct-reading type detectors provided under a previous contract. Studies were conducted to evaluate and demonstrate the availability of stable, portable N02 calibration sources for NO2 instrumentation. The use of selected, commercially available cylinder sources for NO2 instrument calibration were recommended. Additional studies were also conducted to investigate the feasibility of instrumentation for rapidly monitoring CO, NO and NO2 in diesel exhaust.

Jan 1, 1981

By Frank E. Chase, Deno M. Pappas, Christopher Mark

Multiple seam interactions are a major ground control hazard in many U.S. underground coal mines. The two most common types are: • Undermining, where stress concentrations caused by previous full extraction in an overlying seam is the primary concern, and; • Overmining, where previous full extraction in an underlying seam can result in stress concentrations and rock damage from subsidence. The National Institute for Occupational Safety and Health (NIOSH) has completed a major study aimed at helping to identify the location and likely severity of these interactions. In the course of field visits to mines throughout the U.S., more than 300 multiple seam case histories were assembled into the largest data base of multiple seam case histories ever collected. These data were analyzed with the multivariate statistical technique of logistic regression. The study also employed LaM2D to estimate the multiple seam stresses, ALPS and ARMPS to determine pillar stability factors, and the CMRR to measure roof quality. The study resulted in the development of a computer program, called Analysis of Multiple Seam Stability (AMSS), which can help mine planners to evaluate each potential interaction and take steps to reduce the risk of ground control failure. AMSS first evaluates pillar design by calculating the single seam Stability Factor (SFSS) using ALPS or ARMPS. It also automatically generates a LaM2D analysis that provides the additional multiple seam stress so that the final, multiple seam SFMS can be determined. The second part of the AMSS procedure builds upon the statistical findings that overmining is much more difficult than undermining, isolated remnant pillars cause more problems than gob-solid boundaries, and weaker roof significantly increases the risk of multiple seam interactions. AMSS quantifies these effects and predicts the outcome in terms of three levels of risk: GREEN (where a major multiple seam interaction is considered unlikely), YELLOW (where adding a pattern of cable bolts or other equivalent supplemental support could greatly reduce the probability of a major interaction.), or RED (a major interaction should be considered likely, and it may be desirable to avoid the area entirely).

By P. G. Pigott

The lack of technical information regarding the physical characteristics of kaolins and bauxitic kaolins, rejected during the mining of bauxite near Eufaula, Ala., has retarded their commercial utilization. This investigation was undertaken to determine their behavior when used in refractories. Ores were evaluated as refractory raw materials by compounding dry-press mixtures and specialties following procedures common to the industry. Products now on the market were used for comparison in laboratory evaluation.

Jan 1, 1959

By J. R. Thoenen

For several years the Bureau of mines has been investigating the characteristics of ground vibrations produced by quarry blasts. Considerable basic information has been obtained in the course of this study, and the results have been made known to the public through various publications listed in the accompanying bibliography The studies have been confined to obtaining fundamental knowledge of the characteristics of the vibrations themselves, because it was evident at once that he problem was extremely complicated. It was felt that any attempt to predict the effect of a ground vibration on any type of artificial structure would be useless until the complexities of building vibrations are better understood. As opportunity offered, teats wore made in various types of structures and the effects of vibrations from many different sources were measured. In one set of tests (5)4/, it was demonstrated that the behavior of a building as quite different if it was shaken by vibrations originating outside tae foundation walls than if the source of the vibrations was within the building; vibrations coming from the ground outside seemed to shake the building as a single, loosely-coupled structure, whereas mechanically induced vibrations within the house seemed to set floors and walls in motion as independent units, each of which communicated its own natural motion to the adjoining member, causing a very complicated movement that was impossible to interpret.

Jan 1, 1938

By Wilbur I. Duvall

In a review of so 40 papers on damage to residential structures resulting from blasting, only 3 were found that present data on the observed amplitude and frequency of the vibration levels produced by blasting together with an observed degree of damage to a residential structure. The data from these three reports have been analyzed statistically to determine if one of the quantities, displacement, velocity, or acceleration, is more reliable than the others for estimating the degree of damage to a residential structure. From this analysis the conclusion is drawn that a given degree of damage to a structure is most closely related to the magnitude of the particle velocity of the wave motion passing thru the earth at the structure location. On the average, only minor damage it observed for peak particle velocities of 5.4 inches per second, and major damage is observed for peak particle velocities of 7.6 inches per second. When the spread of the data is taken into consideration, the following statement can be made: Wave motions that have a peak particle velocity in excess of 2 inches per second have a fair probability of producing some damage to structures, whereas wave motions that have a peak velocity less than 2 inches per second have a very low probability of causing any damage. Therefore, the recommendation is made that vibration levels in the vicinity of residential structures should be maintained below a peat particle velocity of 2 inches per second. The above criterion for safe blasting is considered to hold over a wide variety of soil and rock conditions because the original data were obtained for a wide range of soil and rock conditions and on various types of residential structures. INTRODUCTION Ever since explosives were discovered and developed for mining purposes, there has existed the problem of what effects the air and ground vibrations resulting from blasting have on structures of various types. This problem is

Jan 1, 1962

By G. N. Schrauzer

Work has been carried out in the development and testing of carbon monoxide (CO) detection devices which use silica-gel impregnated with metal salts. If carbon monoxide is present, the ?detection gel? (the treated silica-gel) changes from a yellow to a blue-green or blue color. The detection gel "regenerates", i.e., returns to its original yellow color, within 4-24 hours after removal from air containing CO. The detection gel exhibits a threshold of CO response which can be adjusted over a wide range of CO concentrations, typically from 50-500 ppm in air. The preparation of detection gel using salts of palladium, molybdenum and copper is described. Also reported are the results of testing the detection gel&apos;s response to carbon monoxide under varying conditions of temperature and humidity and in the presence of some potentially interfering gases. Low levels of hydrogen sulfide (~ 5 ppm)1 nitrogen dioxide (< 7 ppm), and acetylene (> 200 ppm) were found to affect the detection gel. Temperature and humidity were also found to affect the detection gel&apos;s response. Increasing temperature shortens the gel?s response time while increasing the humidity delays the gel?s response and alters the threshold of the gel. A brief discussion of the further research and development necessary to stabilize the detection gel?s desirable characteristics is included. Descriptions of testing equipment and procedures are covered in detail.

Jan 1, 1978

By J. J. Forbes

Ventilation is the most important safety factor in the production of coal because on it depends the safety, health, and efficiency of those who work underground. Without adequate and efficient means of supplying fresh air to the working faces, mining could not have advanced as it has. The extent of the workings, the increase in mechanization, and the increasing use of electricity are largely responsible for changes in methods of ventialtion. Ventilation in the early, days of coal mining was accomplished by means of a natural draft, created principally by a difference in the weights of columns of air between the intake and return openings: Later the furnace was introduced for the purpose of increasing the quantity of air in circulation. Mines continued to become larger, their output increased, men were employed in greater numbers, and more fresh coal surfaces were exposed. Coal beds near the surface, and practically free from explosive gas became exhausted, and deeper beds that liberated methane were opened as development advanced. Mechanical ventilation became necessary and was first accomplished by disc-type steam driven fans she old-.fashioned steam driven disc fan has generally been supplanted by the powerful electrically operated centrifugal fans in use at modern coal mines. In order to be secure against gas explosions and provide ample fresh air for persons employed in large coal mines, air must be conducted through the mine to all working places and to all other unsealed parts of the mince in sufficient quantities to dilute and render harmless all dangerous and noxious gases.

Jan 1, 1929

By J. R. Thoenen

For several years the Bureau of mines has been investigating the characteristics of ground vibrations produced by quarry blasts. Considerable basic information has been obtained in the course of this study, and the results have been made known to the public through various publications listed in the accompanying bibliography. The studies have been confined to obtaining fundamental knowledge of the characteristics of the vibrations themselves, because it was evident at once that he problem was extremely complicated. It was felt that any attempt to predict the effect of a ground vibration on an&apos; type of artificial structure would be useless until the complexities of building vibrations are better understood. As opportunity offered, teats wore made in various types of structures and the effects of vibrations from many different sources were measured. In one set of tests (5)4/, it was demonstrated that the behavior of a building as quite different if it was shaken by vibrations originating outside tae foundation walls than if the source of the vibrations was within the building; vibrations coming from the round outside seemed to shake the building as a single loosely-coupled structure, whereas mechanically induced vibrations within the house seemed to set floors and walls in motion as independent units, each of which communicated its own natural motion to the adjoining member, causing a very complicated movement that was impossible to interpret.

Jan 1, 1938

By Michael G. Zabetakis

The spillage of liquid diethyl ether in rooms at floor level and 3 feet above the floor resulted in flammable vapor-air mixtures in the immediate vicinity of the exposed liquido The liquid temperature was found to decrease by as much as 35° C., with a resultant decrease in vaporization rate. A search of the literature yielded numerous references to unstable peroxide (residue) formed by the autoxidation of ether. Such residues appear to constitute an explosion hazard in the condensed state.

Jan 1, 1962

By Thomas J. Peters

In 1984, at the request of the Bureau of Land Management, the Bureau of Mines studied 7,000 acres of the 9,240-acre Little Blitzen Gorge Wilderness Study Area in Harney County, OR, to evaluate its mineral resources. The study area is dominated by a 1,500-ft-deep canyon that was carved by Pleistocene glaciers in gently westward-dipping homoclinal flows of Miocene Steens Basalt. The Bureau reviewed pertinent literature and county mining records During the field investigations, 18 rock samples were collected from basalt dikes, breccia, fractured or porphyritic flows, and 20 alluvial samples from gravel accumulations. Mercury anomalies from sampling by the Oregon Department of Geology and Mineral Industries could not be verified. The mercury might have originated -From the Pike Creek Formation, a known mercury-producing unit that may extend into the study area beneath the Steens Basalt. Any epithermal deposit at depth would be expensive to explore and develop.

Jan 1, 1986

By R. W. Dougherty

From time to time interest has been evidenced in transporting coal with water in pipe lines. About the year 1895, United States patents broadly covering a method of pumping coal with water through pipelines were granted to W. C. Andrews. His process was used to some extent in pumping anthracite culm and waste back into the worked-out portions of the mines. About 1905, W. T. Donnely was granted patents relating to pumping anthracite silt away from the breakers. From about 1913 until 1924, a British engineer, Gilbert G. Bell, used a short pipeline to convey coal with water from barges on the Thames River to the Hammersmith Electricity Generating Station, London. Minus 5-inch coal was transferred 660 yards through an 8-inch pipe. Some trouble was experienced with fine coal, which tended to plug the line. Bell made several proposals to transport coal by pipeline overland from the Midlands to London, a distance of about 100 miles, but these were never adopted. This survey is concerned mainly with the problems presented by actual pipeline transportation of coal with water. It is assumed that the coal will have been processed to remove most of the abrasive impurities by conventional methods prior to introduction into the line, and that it has been crushed to the required top size. Dewatering at the discharge end of the line is considered part of the conventional cleaning process. There still remain many pump-performance and behavior of water-coal mixture problems that can be solved only by actual performance tests. It is recognized that the distribution of coal to other than very large users is not changed. Large storage areas would be required to supply seasonal markets. Large users, such as power plants and heavy industries, could be supplied by branch lines directly to the point of use, It is also recognized that pipe lines might not be able to carry a full range of sized coal to meet market demands in many areas.

Jan 1, 1951

This report describes the activities and publications of the Bureau of Mines Health and Safety Research and Testing Center, Pittsburgh, Pa., for the fiscal years 1960-65. It includes a discussion or work being conducted on roof control, dust explosions, ventilation, health, coal mine fire control, and electrical-mechanical testing, and an abstract of each paper published during the report period.

Jan 1, 1966