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By X. B. Starnes

"INTRODUCTION The Eva Tanguay property is in Crittenden County, Kentucky, about 1 mile south or the village of Mexico, and can be reached from Marion, the County seat, by travellng south on State Highway 91 for 6.8 miles and then turning southwest on State Highway 70 and traveling 2 miles farther.Although the property lies between the Huffaw and Pigmy properties, which together have produced 200,000 tons of fluorspar ore, production from the Eva Tanguay has been estimed at only 1,000 tons. Geological factors on the property indicated the likelihood of an ore occurrence, and the author examined the property in April 1944. Shortly thereafter, the U.S. Geological Survey wrote a report on the property, which was not published. A drilling program was initiated by the Bureau of Mines November 1, 1944, and continued until eight holes totaling 3,137.5 feet were drilled.The holes showed that the Tubb fault system on the Eva Tanguay property is composed of three members, all of which contained commercial ore. The line dividing the Haffaw and Tanguay properties crosses the vein outcrops, causing a part of the ore indicated to be on each property.The mineral rights, which are leased by Robert Frazer of Marion, are owned by Mrs. O. S. Denny and W. C. Bohn, both of Marion."

May 1, 1947

By Thomas J. Fisher, John J. Sammarco, Gary L. Mowrey, Edward F. Fries

This report (Safety File 3.0) is the fourth in a nine-part series of recommendations addressing the functional safety of processor-controlled mining equipment. It is part of a risk-based system safety process encompassing hardware, software, humans, and the operating environment for the equipment’s life cycle. Figure 1 shows a safety framework containing these recommendations. The reports in this series address the various life cycle stages of inception, design, approval and certification, commissioning, operation, maintenance, and decommissioning. These recommendations were developed as a joint project between the National Institute for Occupational Safety and Health and the Mine Safety and Health Administration. They are intended for use by mining companies, original equipment manufacturers, and aftermarket suppliers to these mining companies. Users of these reports are expected to consider the set in total during the design cycle. • 1.0 Safety Introduction.—This is an introductory report for the general mining industry. It provides basic system/software safety concepts, discusses the need for mining to address the functional safety of programmable electronics (PE), and includes the benefits of implementing a system/software safety program. • 2.1 System Safety and 2.2 Software Safety.—These reports draw heavily from International Electrotechnical Commission (IEC) standard IEC 61508 [IEC 1998a,b,c,d,e,f,g] and other standards. The scope is “surface and underground safety-related mining systems employing embedded, networked, and nonnetworked programmable electronics.” System safety seeks to design safety into all phases of the entire system. Software is a subsystem; thus, software safety is a part of the system’s safety. • 3.0 Safety File.—This report contains the documentation that demonstrates the level of safety built into the system and identifies limitations for the system’s use and operation. In essence, it is a “proof of safety” that the system and its operation meet the appropriate level of safety for the intended application. It starts from the beginning of the design, is maintained during the full lifecycle of the system, and provides administrative support for the safety program of the full system. • 4.0 Safety Assessment.—The independent assessment of the safety file is addressed. It establishes consistent methods to determine the completeness and suitability of safety evidence and justifications. This assessment could be conducted by an independent third party. • 5.0 Safety Framework Guidance.—It is intended to supplement the safety framework reports with guidance providing users with additional information. The purpose is to assist users in applying the concepts presented. In other words, the safety framework is what needs to be done and the guidance is the how it can be done. The guidance information reinforces the concepts, describes various methodologies that can be used, and gives examples and references. It also gives information on the benefits and drawbacks of various methodologies. The guidance reports are not intended to promote a single methodology or to be an exhaustive treatment of the subject material. They provide information and references so that the user can more intelligently choose and implement the appropriate methodologies given the user’s application and capabilities. [ ]

Jan 5, 2002

By H. H. Lowry

Abstracts of papers on low-temperature tar published since 1942 are included in this selected bibliography. Abstract journals -including Chemical Abstracts, Fuel Abstracts, and B.C.U.R.A. Monthly -have been consulted through 1957. Abstracts of papers on low-temperature carbonization are not included unless information is given on composition, economics, processing, or utilization of the tar; thus, papers reporting only yields of tar from assay tests, pilot plants, and commercial operations are excluded. Listing in the bibliography is alphabetical by authors; arrangement under each individual is chronological. Secondary authors are cross-indexed to the main entry. The subject index uses the main entries: Composition, economics, processing, and utilization with appropriate subheadings. A code letter following the abstract number indicates the country where the paper originated.

Jan 1, 1959

By F. P. Haver

The Federal Bureau of Mines investigated aqueous electrolysis as a means for reducing lead chloride prepared by ferric chloride leaching of galena concentrate: NaC1 PbS + 2FeC13 ? PbC12 + 2FeC12 + S°. During electrolysis, metal was produced from solid lead chloride in contact with the cathode rather than from lead in solution. Relatively high current densities--up to 300 amp/ft2--were possible when operating in this way. A very simple cell, having a horizontal lead cathode at the bottom and a vertical graphite anode at the top, was employed. Lead chloride crystals, covering the cathode, were converted to metal powder during electrolysis, and chlorine gas or FeCls was produced at the anode, depending on the electrolyte composition. Electrolytes tried included aqueous solutions of HCI, NaCl, NH4Cl, and FeC12-NaC1. Optimum results (96-pct current efficiency, 0.23 kwhr/lb Pb) were obtained with 20 pct HC1 at 25° C, using a current density of 15 amp/ft2 and an electrode spacing of 1 inch. When the current density was increased, the energy requirement increased also but only to 0.41 kwhr/lb at 150 amp/fr3 and 0.58 kwhr/lb at 300 amp/ft2.

Jan 1, 1978

Develop a reliable, portable device for non-destructively testing the support integrity of a friction rock support (commonly referred to as a Split Set ). Approach The friction rock support, used to support mine roof and ribs, is a slotted tube driven into a drilled hole of smaller diameter. Upon installation, the tube is compressed radially. The amount of compression is a function of the hole diameter, the strength of the host rock, and the properties of the split set itself. A simple lightweight self-contained device was developed to determine the pull-out resistance of the friction rock supports in-situ, based on measurements of the tube's deformation. The tester measures the com-pressed internal volume of the slotted tube, which has been found to provide an estimate of the support's resistance to pull out. How It Works The tester consists of a pump and expander sections. The expander sections are made from an elastomer membrane which is stretched over two cores, each one inch in diameter and twelve inches long. The expanders are connected by a flexible coupler so that they can fit any alignment of the support.

Jan 1, 1984

Develop a technology for producing high-quality hake graphite from the steelmaking waste known as kish. Approach Treat the waste kish as an ore and apply mineral processing techniques of physical beneficiation and chemical purification to produce a range of graphite products com¬petitive with the natural mineral. Background Graphite is a naturally occurring form of carbon with a unique combination of properties that make it indispensable in a very wide range of industrial and consumer applications. It has high electrical and thermal conductivity and remains stable to extremely high temperatures It has a low coefficient of friction and is nearly impervious to corrosion. The steel industry is dependent on graphite in clay-, magnesia-, and alumina-bonded refractories for crucibles, bricks, facings, and coatings. Electrical uses include graphite brushes in motors and generators, and electrodes in batteries. The transportation industry needs graphite for clutch and brake linings, and all industries depend on graphite in seals, gaskets, lubricants, and coatings. The consumer sees graphite in composite plastics and in the common pencil. As with all natural minerals, the availability of graphite is diminishing and costs are rising as quality decreases.

Jan 1, 1993

By M. J. Ankeny, J. J. Forbes

Several sets of questions and answers on the fundamentals of first aid to the injured, based on the Manual of First-Aid Instruction of the United States Bureau of Mines, are now in use in various parts of the United States. Persons experienced in first-aid instruction believe that a standardized set of questions and answers will assist materially in preparing men for examin- ations conducted by the Bureau for first-aid certificates. Inquiries as to whether a set of standardized questions and answers is available have been made frequently by those training men for the Bureau of Mines examination for certificates. It is believed that the following list of 171 questions and answers com- piled directly from the manual will be useful to company officials and em- ployees who are engaged in cooperative first-aid training to qualify for Bureau of Mines certificates. The list may also be used by field men of the Bureau in training instructors preparatory to a cooperative training campaign and in examining classes or individuals for first-aid certificates. The page references in parentheses refer to pages in the Manual of First-Aid Instruction.

Oct 1, 1935

By Robert P. Vinson, John C. LaScola, Fred N. Kissell, Edward D. Thimon

The face ventilation measurement method developed by the Bureau of Mines involves releasing a small volume of tracer gas (SF6) on the off-curtain side of the working face at the start of the mining cycle. At the same time, gas bottle samples are taken in the immediate return airway. The gas samples are analyzed, and a curve is drawn of SF6 concentration versus time. From this curve, the percentage of gas removed per time is calculated. A curve showing a high percentage of the tracer gas removed in a short period would represent a well-ventilated face. The face ventilation measurement method was tested in a full-scale mine entry model. Subsequently it was used underground to evaluate the spray-fan ventilation system and in an MSHA test facility to test machine-mounted scrubbers. The method was shown to be a simple and effective way of evaluating face ventilation systems.

Jan 1, 1980

By M. J. Ankeny

All bituminous-coal mines, by the nature of their product and inherent gassy tendencies, are subject to explosions or mine fires. The evolution from large, hand-loading sections employing numerous men and containing open-type equipment, lights, and nonpermissible explosives to small, concentrated mechanical sections with but few well-supervised men utilizing modern preventive equipment has not altered this premise. Mine catastrophes such as Centralia and New Orient No. 2, as well as recent disasters of less magnitude, have refuted the trend of thinking that modern equipment, will prevent or localize explosions and prevent widespread or loss of life.

Jan 1, 1952

By F. W. Penn

An aircraft auxiliary power unit (APU) was used as an exhaust source for evaluation and refinement of sampling and analytical procedures for gas turbine engines. The unit was also used to determine the emission characteristics of APU's in service and to study the effect of fuel composition and combustor design on exhaust emissions. Carbon monoxide, carbon dioxide, oxides of nitrogen, hydrocarbons, aldehydes, particulate loading, and odor were measured at engine operating modes representing the duty cycle encountered in airline operation. Analyses showed good repeatability, and adequate sensitivity was attained in these experiments. Smoke opacity measurements were not taken owing to the lack of a high-sensitivity smokemeter. Results showed that the minimum emission levels occurred with the standard combustor and Jet A fuel. Emission rates were highly dependent on test mode, but emission patterns as a function of test mode were similar for all fuels and combustors tested. A comparison of three identical design production combustors showed a variation in average emission rates of less than 5 pct.

Jan 1, 1973

By H. Robert Ensminger

The Belizean economy had an estimated annual growth of about 3.4% over that of 1986. Economic growth during the 2 previous years was slower and was characterized by a negative trade balance. The gross domestic product (GDP) was an estimated $200 millioni2 in current dollars. Limited natural resources and scarce finances continued to make the Government's task a difficult one. Belize and China signed an economic cooperation agreement in April under which the Chinese Government is to provide technical assistance, a cash grant of $60.000, and a long-term, interest-free loan of approximately $1.5 million. In May, it was reported that gold was discovered in a remote area of the Maya Mountains in western Belize. An estimated unassayed value of $400 million has been placed on the deposit by one of its discoverers. However, the government in Belmopan has played down the discovery. Two U.S. oil companies. Seahawk Oil International of California and Alston Oil Co. of Texas, were granted licenses to explore for oil. Seahawk Oil will explore a large area of the Orange and Corozal Districts, while Alston Oil will prospect a 90,000-acre area of the western Cayo District. Another U.S. oil company, Pecten Oil Co., recently completed seismic studies off-shore of Belize City. Pecten Oil has made plans to start drilling in 1988.

Jan 1, 1989

By J. H. Maysilles

The Bureau of Mines is examining a variety of low-grade uranium ores because projections indicate that an appreciable percentage of future U.S. uranium production will be derived from resources containing 0.01 to 0.1 percent U308. One possible source is represented by a granitic material from Wyoming; the available samples contained 0.06 and 0.12 percent U308. Tests were conducted to explore the general leaching characteristics of this potential resource. The material responded to both acidic and alkaline leaching techniques. Conventional acid leaching extracted 93 percent of the uranium in 18 hours; the required acid addition was 50 to 100 pounds of H2S04 per ton of ore, and the oxidant addition was 3 pounds of NaCl03 per ton of ore. The acid consumption continues after maximum uranium recovery has been reached; this effect may complicate heap or in situ leaching with acidic solutions. Some variation in reagent requirements was noted between the two ore samples. Conventional carbonate leaching with strong solutions at 85° C extracted 94 percent of the uranium in 24 hours. These granitic materials also showed some response to dilute carbonate solutions, and the results suggest that the material may be chemically amenable to heap or in situ leaching with dilute carbonate solutions.

Jan 1, 1977

By Dave P. Cooper, Tim D. Burgess, Dean H. Ambrose

This paper discusses the application of digital human models (DHM) to examine computer generated forces necessary to move specific joysticks by using roof bolter virtual operators to predict the forces experienced on the operator’s upper extremities. Using DHM and simulations of static movements, investigators analyzed predictions of joint moment and joint force effects on virtual operator’s right wrist, elbow and shoulder and compared them to different body dimensions and work postures. This study exemplifies the ease of estimating upper extremity loads on equipment operators using virtual operators and computer models of equipment and work environment. As expected, comparing results of percentage of joint force and moment reduction using the electronic control and of the mechanical control showed that the electronic control had lower joint forces and joint moments over the mechanical control. The average predicted value of the joint moment on the wrist was 1.84 Nm, elbow 7.85 Nm and shoulder 14.55 Nm and of the joint force on the wrist was 5.06 N, elbow 4.56 N, and shoulder 3.67 N. Because the data illustrates low-level forces to move a joystick, inadvertent actuation of the control is addressed. Regardless of the findings, research is still needed on joysticks in real world situations such as an epidemiological assessment of equipment operators in the field before final recommendations and conclusions can be drawn.

Jan 1, 2007

By Doug Tesarik

The study of neutrinos?particles infinitesimally smaller than atoms?would be significantly advanced if a deep underground facility were available that would filter out unwanted cosmic radiation. Encouraging progress has been made in satisfying the criteria for such a facility with the selection of the Homestake Mine in Lead, SD, by the National Underground Laboratory Committee as the recommended site for a National Underground Science Laboratory (NUSL). The Homestake Mine is America?s oldest and deepest underground mine, and its well-maintained infrastructure to depths of 2438 m below the surface makes the mine an excellent site for such a laboratory. The investigation reported here is an initial study of the stability of the first of the proposed chambers. A cylindrical room with a dome-shaped roof and floor was analyzed in three dimensions using the finite-difference program FLAC3D. The results were compared to recommended support requirements based on Barton?s Tunneling Quality Index, Q. Based on model results and observations from previous mining studies, large rooms with 50-m roof spans can be constructed and will remain stable at 2141 m below the surface in the Poorman Formation when the rock is reinforced with cable bolts. Construction may be possible at lower levels in the Yates Formation if more extensive laboratory strength tests confirm initial results.

Jan 1, 2002

By Eugene Baker, Joseph Cervik, Albert Sainato

In Europe, water infusion is used widely to reduce generation of respirable dust during mining. Its use in the United States is limited to a few plow operations in the Pocahontas No. 3 Coalbed. This Bureau of Mines report describes the technology for infusing water in to a longwall panel and reports the results of a recent demonstration in the Lower Sunnyside Coalbed that achieved dust reductions averaging 58 pct. Because water infusion increases moisture content of the coalbed, face air velocities in excess of 500 ft/min (2.5 m/s) are possible, further diluting dust levels before dust entrainment occurs. An economic analysis shows a 23-pct reduction in operating costs when coal production is increased by changing from unidirectional mining to bidirectional mining with water infusion.

Jan 1, 1983

By L. D. Tracy

For many yeirs natural gas has been the principal fuel used in the he·1 ting furnaces in those mills located in the. Pi t-c;s. b.urgh district· \7hich manufacture bolts ., nuts, rivets, pick$, mattocks and srr.&11 for6ine;s. For a nUI.1"'.::>er of years the steady supply of this fuel has been more or less interrupted owing to the increased4and f·or d9mes tic use and to the increasing difficulty in securing an ad.eq_ua te c.1mount of natural gas. This condition has led a number of the steel compa.nies to substitute -oulvsrized coal a.s a fuel for the.furnaces. Elaborate irista.llations have been made for pulverizing tne coal ar!d _ coriveyi16 i -c to the fur:waces. • Soon after the furnaces ·-:commenced .. to operate ·,Vi th :pulverized coal, large quanti ties O::f.' fine dust beg.::in to accumulate on the platforms over the fu:rna. ces, the. roof trusses, on the outside of the va.rious· pip·e ·line electric cables a.i.1.d even on the roofs of the buildings. Some of tha comi:,a.n:;.0s, becomin·g alarmed, requested the Bureau of ;Unes to rr.c1ke an investigation to ascertcliin the.· licibili ty of this dust to cause an explosion.· Nhi le conducting this inves ti ga ti on,· an explosion· occurr-2! d in a.nothe:2 nill ·,7hich caused he death of one man and severely burned t;io others. Eleven sc1nrcles of the dust (which for convenience has been termed "mill d.ust 11 ) from various locations in the different mill' buildings were taken and submitted to chemical analyses, microscopic examination and also to flame and explosion tests. From the chu,1ica.l analyses it was found that· the volatile matter in th..:: dusts xanged -from 6.3 per cent to 23,54 per cent, fixed carbon from 50.88 per cent to 67.08 per cent and ash from 32.29 per cent to 32.16 per centw

Dec 1, 1919

By T. H. Davis

Twelve laboratories from the Western United States and Canada participated in radon progeny intercomparison measurements at the U.S. Bureau of Mines radon calibration facility in March 1987. The participants intercom pared grab-sampling and automated equipment methods at high and low concentrations of radon progeny and condensation nuclei (CN). The objective of this intercomparison was to determine if the measurement procedures and equipment of the North American facilities are equivalent. The sampling results showed good agreement among all participants. The standard deviation for the working level measurements was less than 3.5% for 1.70 working level (WL) and less than 8.8% for 0.21 WL. This relatively good agreement was achieved by using alpha standards calibrated by National Bureau of Standards (NBS) and by closely checking and monitoring airflows.

Jan 1, 1989

By Maria I. De Rosa, Charles D. Litton

The National Institute for Occupational Safety and Health (NIOSH/PRL) con­ducted a series of large-scale experiments to evaluate the effectiveness and safety of various concentrations of an inert gas mixture (CO2,8%;N2, 50%; Ar, 42%) for preventing and sup­pressing cab ?res. Comparison of concentrations effectiveness in yielding safe times has led to the choice of an optimum gas mixture concentration, discharged in the cab through a muf?ed nozzle system, for the development of a dual cab ?re inerting system. Of note is that safety training programs, including the synchronization of performed tasks, need to accompany this technology to enhance operator’s ef?ciency and safety during ?re emergencies within the safe times yielded by the cab ?re inerting system. Cab ?res are caused by the ignition of ?ammable vapors and mists (ball of ?re) that penetrate the cab during prolonged hydraulic ?uid and fuel ?res, and electrical malfunctions involving other cab combustible materials. Often, these ?res force the operator to exit the cab under hazardous conditions during a time needed to perform emergency tasks. Hence, it is important to provide the operator, not only with an engine fire suppression system (dry chemical powder), but also with a cab ?re protection system, effective both in preventing the ignition of ?ammable vapors in the cab, and suppressing cab material ?res.

By J. B. Gayle

Because economic and geographic factors have focused particular attention on the use of anthrafines in blends containing Lower Kittanning coal as the low-volatile component, samples from this particular bed were selected for experimentation whenever practical. Carbonizing tests were carried out in accordance with standard procedures, using the Tuscaloosa and sole-heated ovens. Most of the results are in general agreement with those reported by previous investigators. Specific findings are as follows: (1) The effectiveness of anthrafines in reducing coal expansion is such that even highly expanding, low-volatile coals can be carbonized safely with suitable additions of anthrafines and careful control of charge density. (2) Increases in coke size, resistance to shatter, and apparent specific gravity appear to be characteristic for additions up to approximately 15 percent to a fixed base blend. When anthracite of minus-48-mesh size was used and the proportion of low-volatile coal simultaneously increased, these indexes increased only slightly or remained substantially constant. (3) No increase in breeze formation was noted for additions in amounts up to 15 percent. (4) Abradability of coke was increased by additions of anthracite of No. 5 Buckwheat size, but it either decreased or remained sub¬stantially constant when the inert was ground to pass a 48-mesh screen.

Jan 1, 1956

Increase the safety of underground mine workers by minimizing hazards associated with rerailing mine cars after derailment. Background and Approach A serious operational problem in underground mines is the task of rerailing mine cars. Current rerailing practices are not only hazardous but are inefficient as well. Most methods involve pulling the derailed car back onto the track with a locomotive. This causes damage to the road bed and is not effective on curves or in situations where the car's wheels are too far from the rails. Jacks, wooden props, and pry bars are also used to raise or lower cars back onto their tracks but methods involving these tools require much strenous manual effort by mine workers, thus posing possible serious injuries. The problem is further compounded by the cramped, narrow confines of the underground mine environment which allows no space to permit use of cranes or other surface railroad rerailing techniques. The Bureau of Mines, aware of these problems, investigated improvements in current underground rerailing methods. Through a cooperative effort with Hoesch MFD, a system was designed and modified that can be easily carried into the mine by workers and quickly assembled at the derailment site. The system is hydraulically and pneumatically powered rather than reliant upon manual operation.

Jan 1, 1986