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By C. Ogasawara

This document describes the direction and progress of the Bureau of Mines Oil Shale Mining Environmental Research Program as of January 31, 1979. It is aimed at focusing the Bureau's role in environmental research supporting oil shale development with respect to the activities of other involved government agencies and private industry. Environmental considerations in oil shale extraction, such as ecological disturbances, health and safety hazards, waste management, and socioeconomic impacts, are discussed along with the type of research known to be planned by organizations to ameliorate these problems.

Jan 1, 1979

By H. B. Carroll

This Bureau of Mines report evaluates the performance of commercially available portable instrumentation for the detection of carbon monoxide, carbon dioxide, oxygen, and methane at conditions simulating an industrial work atmosphere. Portable instrumentation included in the study was gas-detection tubes (length-of-stain and color intensity), catalytic detector, liquid absorption detectors, paramagnetic oxygen detector, galvanic detector, and pelement or hot-wire methane detectors. Evaluation of the instruments was in atmospheres with 50 and 80 percent relative humidities at 75° F and containing test gas concentrations of 0.1, 0.25, 0.50, 1.0, 1.5, and 2.0 times the thresh-old limit value. Correlation of the results from the portable gao analyzer with measurement from the standard instruments was made by calculating and plotting an estimated line of regression, prediction, and confidence limits and the correlation coefficient for each detector system. Relative humidity in the 50-to 80-percent range did not appear to contribute to instrumental uncertainties in either performance or operation. Considerable deviation in detection precision between the portable gas-detection systems and the standard systems was established, especially at the lower gas concentration levels. The main difference or inconsistency in toxic gas concentrations determined with length-of-stain tubes resulted from the observer's interpretation of the results rather than difference in the tubes themselves.

Jan 1, 1973

By David Bendersky

This report covers a technical and economic investigation of old electrical power systems, equipment and practices being used in the metal/non-metal raining industry. The principal sources of information were the MSHA District offices, visits to representa¬tive mines and mills, equipment manufacturers and the literature. A list of 85 mines and mills, submitted by the MSHA Districts as candidates for this study, is given and their characteristics are analysed. The electrical power systems and practices at the 10 mines and 9 mills which were visited are described. The principal areas which do not conform to standard electrical practices are discussed with emphasis on the safety aspects of these practices. The costs to update electrical power systems and practices in metal/non-metal mines and mills are given. The principal findings of the study are summarized and recommendations are submitted.

Jan 1, 1980

By Joseph Gersic

MINFO has been developed to serve as a frontend for three databases created to store basic minerals information gathered during the minerals resource assessment conducted by U.S. Bureau of Mines(USBM) for the Malheur and Jordan resource areas of southeastern Oregon(MJRA). The primary database is the Minerals Location Inventory (MLI.DBF) which contains of information assembled from field work performed during this project, the USBM Minerals Availability System/Mineral Information Location System(MAS/MILS) database, the Oregon Department of Geology and Mineral lndustries(DOGAMT) Mineral Information Location(MILOC) database, and the U.S. (Geological Survey(USGS) Mineral Resource Database System(MRDS), In addition, assay results are contained in the geochemical database (ELEMENTS.DBF) and modified X-ray diffraction analysis information is contained in the minerals database (MINOR.M.DBF). MINFO includes four types of program modules: ? Enter/Edit Data was developed to allow the addition of new information and to encourage correction of errors by providing a convenient means of entering and editing data and a large degree of automatic checking and filtering of entries. ? ACAD/DBF Link links each site symbol posted on the map in the drawing file to a record in the database. This provides the user with the ability to use a mouse or other pointing device to graphically select a site for viewing and editing. Edits are performed directly in the database file, ? Reports contains 7 formats of data output for creating files for printing, transfer to other database formats, and exporting to other software packages such as spreadsheets and word processing programs. ? Maps includes 5 programs for creating AutoCAD script files which can be used to create maps of selected information in conjunction with AutoCAD. Mineral location mapping files derived from MLI.DBF can be created in 2 formats. Mapping files can be generated from each of the 2 sets of geochemical analyses contained in ELEMENTS.DBF. X-ray diffraction analyses can also be translated into instructions for creating and posting piecharts at sampling sites.

Jan 1, 1994

By R. Stefanko

This first Annual Report covers the work on Contract No. H0377043 "Cable for Face Equipment", from August 1, 1977 to July 31, 1978. It reports the progress in the three areas of over-and short-circuit protection, cable ampacity research and cable couplers. Field trips have established many interesting facts related to circuit breaker settings and cable size. For example, the determination of cable sizes depends on the RMS duty cycle current determined by a particular piece of equipment, but the actual selection of the cable to be used is often a function of the maximum allowable circuit breaker instantaneous settings as specified in Title 30. In order to avoid nuisance tripping as a result of instantaneous starting current field, laboratory and analytical studies are being conducted to determine proper settings and cable sizes Also an extensive program has been established to monitor the performance of high voltage cable couplers and determine their modes of failure. Various equipments are being designed for laboratory testing, and an extensive reeled cable experiment is also under way.

Jan 1, 1978

Objective To develop safety training tools for mine safety and health professionals that fill gaps in currently available materials. Background Over the past 4 years, NIOSH has developed and released a series of training videos targeted at underground mine safety. These videos were developed in close cooperation with the mining industry and safety training professionals and were intended to provide realistic, interesting, effective training to both new hires and experienced miners. The videos cover the mining cycle, starting with the breaking of the rock (Handling Explosives in Modern Mines), making certain the work area is safe after a blast (Rock Falls— Preventing Rock Fall Injuries in Underground Mines), installation of ground supports and recognition of failed supports (Miner Mike Saves the Day), and hauling both ore and materials in the mine (Hazards in Motion). A separate video (Hidden Scars) captures the story of a fatal rock burst through an interview with a miner who nearly died and who lost his partner in the accident. These videos have been extremely popular in the mining industry and are being used across the nation as well as in 18 other countries. Two of them, Rock Falls and Miner Mike Saves the Day, have won Alice Hamilton awards, NIOSH’s highest recognition for Excellence in Occupational Safety and Health, in the Educational Materials category. Approach A recently completed independent evaluation of the SRL mining videos identified five themes that mine safety trainers consider necessary for successful training materials: high quality, credibility, accurate content, effectiveness, and an engaging nature. All of the NIOSH videos were rated very high for each theme. Using these measures of effectiveness, a more difficult challenge has been undertaken. Much has been written in the mining industry about the coming turnover in employment. The average age of miners in the United States is approaching 50, and many of the “experts” will be leaving the industry as they reach retirement age. The mining industry, like many industries involving skilled labor, relies heavily on a master-apprentice relationship between new hires and older miners. New hands learn from experienced miners. Their learning falls into three primary categories—they learn what’s important to know, they learn how to do things correctly and safely, and they learn the culture.

Mar 1, 2002

By James Noll, Sam Janisko

Underground miners are exposed to some of the highest levels of diesel particulate matter (DPM) in the United States. Therefore, it is important to monitor the exposure of miners to DPM, but it can be difficult because of the complex composition of DPM and the number of interferences. Currently, elemental carbon (EC) is used as a surrogate because it makes up a significant fraction of the DPM and is not affected by interferences. Standard measurement methods for EC can be time consuming and only record end of shift results. In this research, a laser absorption technique that enables one to measure EC concentration in near real time was shown to be a beneficial tool. The real time data showed that the fresh air being drawn into a stone mine was not properly reaching the working area and needed to be redirected to decrease DPM concentrations. The real time data also provided a more accurate efficiency ofan environmental cab compared to just using the standard method by detecting the opening of the cab's window and door. The EC optical monitor was also worn by researchers in a mine to show how it can give not only the average concentration for the shift but also reveal when and where a miner is exposed to DPM. Keywords: Laser absorption, diesel, elemental carbon, mining, exposure

By J. S. Miller

The Bureau of Mines conducted surface tests to determine the feasibility of using liquid explosives for underground rock fracturing. The effects of configuration, confinement, length, critical layer thickness, and fracture-propping sand on detonation and explosive propagation velocity of desensitized nitroglycerin were studied, using polymethyl methacrylate and glass-plate reservoirs through lengths from 3 to 12 ft, with explosive-layer thicknesses from 0.1875 to 0.0312 in and in aluminum tubes 8 ft long with diameters from 2.000 to 0.125 in. Interval and continuous detonation velocity data were obtained. Under the test conditions detonation velocity was dependent upon explosive confinement and fracture-propping sand. The detonation velocity of a confined nitroglycerin explosion in aluminum tubes can be reduced by as much as 85 percent, when the tube contains fracture-propping sand. The shape of the reservoir, whether triangular or rectangular, has little effect on the detonation velocity or explosive propagation. The critical or minimum explosive-layer thickness between glass plates, capable of supporting propagation, was 0.0312 in. The presence of a fracture-propping sand in the sheetlike layers increased the critical explosive layer thickness to 0.0625 in. In nitroglycerin-filled and nitroglycerin-sand filled tubes, the minimum tube diameters successfully tested were 0.125 in and 0.375 in, respectively.

Jan 1, 1969

By Joel N. Van Sant

An investigation was conducted to study possible sources of Utah refractory and structural clays that could be used for the manufacture of refractories and light or buff burning heavy-clay products. A field study was made and the clay samples tested to determine their firing characteristics. Results of the Bureau's work indicate many small noncommercial deposits of hypogenic clay occur in igneous rocks. Commercial hypogenic deposits are mostly halloysite clay developed by hydrothermal replacement of limestone. The high firing shrinkage of halloysite precludes its use as a refractory, however, halloysite produced at the Dragon Mine south of Eureka, is used for making oil catalysts. Clays and shales suitable for low heat duty refractory products are found in the Manning Canyon shale, in shales associated with coal bearing rocks, and in the Dakota formation. Some of the clays from the Dakota formation are also suitable for high-duty refractory products.

Jan 1, 1964

By V. B. Dale

San Manuel has been a modern prodigy from its inception to its present status as a block-caving operation producing 33,000 tons per day. The deposit was discovered, prospected, and developed with modern techniques, and nearly all planning was done from results of an extensive drilling program through an average overburden of 670 feet. The Federal Government had a prominent part in the discovery and primary development of San Manuel. The first 17 holes were drilled by the Bureau of Mines, and discovery of the large, low-grade, disseminated copper deposit is credited to the Bureau. A loan fund of 94 million was granted through the Reconstruction Finance Corporation to the San Manuel Copper Corp. for development of the deposit and erection of concentrating and smelting facilities. Then, while the mine was still being developed, the Defense Materials Procurement Agency contracted to buy a large amount of copper at a pegged price.

Jan 1, 1962

By Jerry E. Olson

In 1986, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied part of the 20,071-acre South Fork Wilderness Study Area (OR-005-033) and part of the 8,791-acre Sand Hollow Wilderness Study Area (OR-005-034) in order to evaluate their identified mineral resources. The study areas are located in Crook County, OR, about 58 air miles east from Bend. The areas studied are underlain by Tertiary- and Quaternary-age volcanic and tuffaceous sedimentary rocks. No mineral resources were identified in or adjacent to the study area. Except for common opal and agate occurrences along the northern boundary of the study areas, no mines, prospects, or mineralized zones occur within the study areas. Bentonite is periodically mined less than 1 mi southwest of the Sand Hollow study area boundary. Neither of the study areas has geothermal leases, but both areas are under lease for oil and gas.

Jan 1, 1987

By R. L. de Beauchamp

A preliminary investigation was made of the extraction of chromium from ferrochromium by low-temperature chlorination in the 3400 to 5250 C range. The objective was to devise a method for separating chromium from iron in high-carbon ferrochromium produced from domestic chromite concentrates. The majority of iron was removed as a volatile chloride; chromium was contained in the residue as a nonvolatile chloride, which was separated from carbon and unattacked ferrochromium by dissolution. A small rotary chlorination apparatus was designed, built, and used for the chlorination tests, and samples of commercial-grade high-and low-carbon ferrochromiums were chlorinated for comparison of chlorination characteristics. Low-temperature chlorination of three types of ferrochromium resulted in the removal of 81.9 to 91.6 percent of the iron content as sublimed FeC13. Recovery of chromium in a leach solution of the reactor product varied from 82.4 to 93.1 percent.

Jan 1, 1968

By John A. Johnson

For the purpose of comparing the amounts of dust produced by various mining operations, samples of atmospheric dust were collected during a complete cycle of drilling, blasting and mucking at or near the face of the Bureau's Mount Weather testing adit while the efficiency of several types of stemming in metal-mine blasting was being investigated. ACKNOWLEDGMENTS All gas samples were analyzed in the laboratory of the Bureau of Mines Gas Section at Pittsburgh, Pa.

Jan 1, 1939

By R. R. Sayers

"The number of investigations reported during the past year indicates that control of the health hazard due to abnormal air conditions is still a matter of serious consideration in the mining, metallurgical, and allied industries.Australia. - In an investigation into the health and working conditions of employees in the mining industry of Tasmania and Victoria3, it was found that although pulmonary tuberculosis may occur early in life, silicosis is e disease of slow evolution and does not appear frequently under the ace of 40. A period of at least ten years in the industry was found necessary to produce silicosis, and in no case was the disease found in those who had not worked underground. A very high incidence of silicosis was found in all fields among those who had worked underground 20 years and longer. There was some evidence that silicosis complicated by tuberculosis may occur earlier than uncomplicated silicosis.England. - In a paper presented before the Section on Occupational Diseases of the British Medical Association, Dr. E. L. Middleton, the medical inspector of factories, called attention4 to the occurrence of silicosis in various industries throughout the country.punitive on some quite harmless industries. Thus Middleton says: ""Where the amount of dust is small the action of the phagocytes is likely to be effective, but where it is great . . ."" What dosage is indicated by ""small"" and ""great"" in this connexion? If the meaning of ""small"" were known, would it be correct to go on to say, as he does, ""each successive dose of silica produces a summation of effects""? Then, again, would it be fair to say ""a comparatively brief period of exposure may be the only determining factor""? What, in minutes, hours, or days per week, per month,' or year, is intended by ""a comparatively brief period""? ""Intermittency of the process"" is another expression used in summing up the reasons for and against a standardization of air purity by a gravimetric process or enumeration of the particles; the arguments against such a standardization are, by Middleton, considered strong, but they are by no means convincing to us. A standard has been accepted in respect of the amount of lead in milligrams per 10 cubic metres of air; Dr. Ronald Lane showed in another paper read that adherence to this makes the occurrence of poisoning highly improbable. Mavrogordato has placed on record figures of silica dust at different stages of the improvements in the workings of the Rand mines, and such a control is in constant operation in them today.We emphasize these points because apparently the Government has taken the unusual course of legislating first and postponing inquiry to a later date, as in the ""Various Industries (Silicosis) Scheme, 1939."" The insurance companies also have a considerable interest in the matter of compensation for the silicosis risk. Where exposure - as in the refractories industries, the grinding industries, sandstone industry, and pottery industry - is day in and day out, they rightly demand a premium far higher than for any other disease scheduled under the Workmen's Compensation Act - 5 per cent on the wages bill. row every industrial employer, such as the paint and varnish manufacturer, who has a sack of crushed silica in his store .room, from which he extracts once a week enough to make a paste With spirit and add to his other ingredients in order to give them the necessary ""bite,"" becomes involved, and may have to abandon the use of the material or pay 8 per cent on his wages bill for an absolutely negligible risk.. For meting out justice standardization seems urgently called for."

Feb 1, 1930

By J. C. Edwards, C. C. Hwang

A Computational Fluid Dynamics (CFD) program was used to model buoyancy induced Product-Of-Combustion (POC) spread from experimental fires in the National Institute For Occupational Safety And Health (NOSH), Pittsburgh Research Laboratory (PRL), safety research coal mine. In one application, the CFD program was used to predict spread from fires in an entry under zero airflow conditions. At a location, 0.41 m below the entry's roof at a distance of 30 m from the fire, the measured smoke spread rates were 0.093 and 0.23 m/s for a 30 and a 296 kw fire, respectively. The CFD program predicted spread rates of 0.15 and 0.26 m/s based upon the measured fire heat production rates. Based upon a computation with [c3h3] as the hydrocarbon fuel, a predicted 5 PPM co alert time of 70 s at a distance of 30 m from the fire is to be compared with the measured alert time of 148 s. In a second application, the CFD program was used to analyze smoke flow reversal conditions, and the results were compared with visual observations of smoke reversal for 12 diesel fuel fires. The CFD predictions were in qualitative agreement with visual observations of smoke reversal.

Provide the U.S. mining industry with technology for designing environmentally sound, low-cost in situ leach mining operations to produce copper from small, deep, and/or low-grade copper oxide deposits. Approach Investigate the feasibility of a new mining method--in situ leach mining-as an alternative to conventional mining for copper. Study fundamental leaching technology that will facilitate future commercial operations. Develop guidelines and procedures that will enable mine operators to design and evaluate in situ leach mining operations for any specific copper oxide deposit.

Jan 1, 1989

By R. W. Stahl

An emergency is defined as an unforeseen combination of circumstances that calls for immediate action. When applied to a coal mine, an emergency may call for prompt removal of the men to the surface through travelways other than the haulageway or intake airways, which are generally contaminated with irrespirable air as a result of an explosion or fire. Therefore, maintenance of adequate and travelable escapeways from all working areas of a mine is vitally important insurance against disaster. Several mine disasters could have been avoided if well-defined escape routes had been provided and made known to all mine employees. Such occurrences, unnecessary as they generally are, unfairly indict the industry when only a small segment thereof is involved. As a result of a rather recent disaster, which might not have happened if good escape routes had been provided, the Bureau of Mines decided to delve into the escape procedure to determine (1) what is being done in the industry and (2) what might be done at reasonable cost.

Jan 1, 1962

By Kenneth C. Stewart

The overall purpose of this study was to develop and evaluate, in the laboratory, instrumentation and procedures which might allow for the use of physical measurements of earmuff attenuation which would yield results equivalent to those obtained from psychophysical measures of attenuation. The ultimate goal was to evaluate techniques which might subsequently prove feasible for physical measurement of earmuff attenuation in the field. Current instruments were modified to have a response similar to differrences observed in earmuff attenuation as observed in Volume 1 of the current contract. Mining noise spectra were selected and presented to a single subject seated in a diffuse noise field. The subject wore one of the muffs evaluated in the earlier study and was also fitted with two physical sound measurement systems. A linear system measured the "outside" noise level and a linear system plus "correction" filter measured the "in-side" noise level. These measurements indicated that, under the procedures presented in this report, a laboratory method for measuring earmuff attenuation is feasible and yields results comparable to an extensive psycho-physical procedure.

Jan 1, 1980

By John J. Sammarco

The U.S. Bureau of Labor Statistics reports that the mining industry has the highest average annual fatality rate (31.9 per 100,000 workers) among all major American industry. To address this, a major research program to reduce hazard exposure of miners with computer-assisted mining equipment was initiated by the U.S. Bureau of Mines.1 One application involves the manual process of extracting and hauling coal where operators, in the tight confines of a mine, can be struck or caught by mobile machinery. The approach to remedy this problem uses a guidance system on the haulage equipment so that it follows the machine that extracts coal. This, in essence, involves sensor-based docking of the machines. Sensors that can survive the hostile mine environment of dust, methane gas, and water, play the key role. Computer analysis of the mining machine's movements and empirical machine characterizations were conducted to establish operating requirements and spatial limitations to ensure proper loading of coal into the haulage equipment. These data served in the selection of a sensing system. Various technologies such as scanning laser systems and ultrasonic sensors have frequently been used in other applications but were found unacceptable. However, a near infrared (IR) sensor employing active targets met the requirements. The sensor has a nominal 75° conical field-of-view and a range from 0.1 to 18.0 m. For the single target mode, nominal range accuracy was 4.3% at a distance of 3.56 m. Correction algorithms were generated reducing the error to 0.6%. Airborne dust testing showed less than 0.8% accuracy (worst case) degradation at levels exceeding (by a factor of 7.5) concentrations permitted by Federal law. The sensor can track multiple active targets providing five degrees-of-freedom (DOF) measurements. Using four targets, the nominal range accuracy was 0.4% without correction algorithms. A guidance system for the haulage system to follow the mining machine does not exist commer¬cially. Such a system can reduce fatalities and injuries by current haulage mining equipment, and is a viable alternative to current haulage control.

By F. W. Wood

The Bureau of Mines has sought clarification of the Ti-TiN system by studying the phases formed by diffusion reactions between titanium and titanium nitride. Reaction couples were prepared by embedding pockets of TiN powder in arc-melted buttons of titanium. Specimens were vacuum annealed at nominal temperatures of 800°, 950°, 1,200°, and 1,500° C. Metallographically mounted cross sections from reacted specimens and from some that were not annealed were examined optically, with an electron microprobe, with an election microscope, and by X-ray diffraction. Each annealed specimen contained a segregated core primarily of d-phase material, an ?-phase diffusion layer, an a-phase diffusion layer, and host metal. On the basis of corresponding microprobe analyses, and considering results of certain other research, a new phase diagram is proposed. It contains no qualitative innovations, only quantitative adjustments. Results were also analyzed from the viewpoint of diffusion behavior. Diffusion coefficients calculated for the ? phase were sufficiently scattered that the parameters are very tentative. Nevertheless, the diffusion behavior reported is in reasonable agreement with one of two prior studies if it is assumed that the earlier investigators were mistaken in their identification of the nitride phase in which the diffusion occurred.

Jan 1, 1974