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By M. C. Malamphy

A general description of the activities and results of bauxite investigation by the Bureau of Mines at its bauxite project in Saline and Pulaski Counties, Ark., has been given in Report of Investigations 4251. The tactual data obtained during the project are reported in a series of Reports of Investigations beginning with No. 4251, of which this is the twelfth. The data are accompanied by maps showing the location of holes drilled and the deposits developed. Each area upon which work was done is reported by half townships. Each bauxite deposit investigated was assigned a name and a number for ready reference and identification, and its location and name are shown on the appropriate halt-township map. The description of each half township is followed by a description of each deposit developed in that halt township. The 14 half-township maps and 77 detail maps of the bauxite deposits in this series of reports give the locations and numbers of all the holes drilled on the project except the deep holes drilled to test the geophysical anomalies. The locations of those holes show on figure 13 in volume 1. The descriptions of the deposits developed are followed by complete detailed logs of the drill holes. Many of the widely spaced exploratory holes did not discover bauxite of minable thickness and grade. The pertinent information obtained from the widely spaced exploratory drill holes has been summarized and tabulated, and a table for each half township is given with the discussion covering that area.

Jan 1, 1948

The Bureau of Mines conducted large-scale laboratory copper ore leaching tests to enable improving copper recovery from large dump-leaching operations. This was done by comparing leaching progress when copper was recovered from recycled leach liquor either by cementation or by solvent extraction. Copper was leached from 7-ton ore samples at room temperature using pH 2 ferric sulfate solutions. With are samples containing 11 percent minus 0.5-inch fines, no marked advantage in using either of the copper recovery methods was evident after 416 days of leaching. With ore containing 32 percent minus 0.5-inch fines, solvent extraction of copper was advantageous in that 60 percent of the copper was extracted after 568 days, whereas only 48 percent of the copper was extracted when cementation was used. Less acid was consumed during leaching when solvent extraction, rather than cementation, was used for copper recovery. Iron, contributed by cementation with scrap iron, plugged the ore bed containing 32 percent fines.

Jan 1, 1981

By Walter D. Holland

This is one of a series of instruction guides developed to help instructors present health and safety training courses to workers in the coal mining industry. This course is intended for training those, usually the safety officers, who perform surveys fur inhalation contaminants in above ground work areas. The handbook entitled ?Handbook for Surveys of Inhalation Contaminants in Above Ground Coal Mining and Processing Work Areas? (NTIS #PB-243-35";) is used as a manual for the course and as a prime reference when performing the actual surveys or interpreting the sampling results. There are six experiments for the students to perform during the course to familiarize them with the sampling devices routinely used during the surveys.

Jan 1, 1976

By Richard F. Hewlett

An attempt has been made to fit assay data from an underground copper deposit to a three-dimensional polynomial surface as a means of expressing assay points in terms of their mine coordinates by a mathematical equation. The resulting equation was evaluated to predict the grade trend of the deposit. Although the fit obtained by this initial experiment is not considered accurate enough to provide good predictions about the deposit, the methodology is presented in this preliminary report to show the potential usefulness of the technique in mineral deposit evaluation. The technique also should be useful in determining the grade of blocks of ore for production scheduling and blending problems in open pit operations. Further experimentation is needed to increase the reliability of the computer program, to increase the precision of the method, and to make the solution more flexible for use on other mineral deposits.

Jan 1, 1964

By M. S. Seehra, R. S. Pandurangi

"INTRODUCTION Silica and kaolin (a layer aluminosilicate) are among the major constituents of most coal mine dusts.' Whereas kaolin is cytotoxic in vitro but nonfibrogenic in vivo in humans and experimental animals,2-4 the cytotoxic and fibrogenic potential of silica is rather well established.5 Wallace and co-workers 6-8 have studied the cytotoxic potentials of both native and surface-modified silica and kaolin and inferred that retoxification is slow in the case of occluded silica vis-à-vis native silica. Recent epide¬miological studies indicate that silica concentration alone in a mine dust, as determined by transmission IR spec¬troscopy (TIRS), does not correlate well with the pro¬gression of coal workers' pneumoconiosis. 9 This obser¬vation has led to the suggestions that silica particles occluded by clays such as kaolin may not be fibrogenic. This proposal requires accurate estimations of kaolin, silica, and occluded silica. The current method of silica analysis in a mine dust sample employs TIRS of the 797- cm -1 band of silica, although its accuracy, as well as that of x-ray diffraction studies, is no better than 25 % , even in a laboratory-generated dust.° In this paper we have employed the techniques of diffuse reflectance spectros¬copy (DRS) and photoacoustic spectroscopy (PAS), in conjunction with an FT-IR spectrometer, for the quan¬titative determination of silica in laboratory-generated silica-kaolin mixtures.One of the main advantages of DRS and PAS is that, in these techniques, problems arising from sample prep¬aration of the KBr-based disks used in TIRS are avoided. There are, however, several other considerations (e.g., particle size effects and saturation phenomenon) which complicate the use of DRS and PAS for quantitative work. 10-25 In this paper, we have carried out a systematic comparison of the quantitative abilities of the two tech¬niques, as applied to the silica-kaolin mixtures, with par¬ticular attention to the saturation behavior of several bands with different absorption coefficients. In particular, we show that a weaker band for silica at 1875 cm-1 is suitable for quantitative purposes, and that quantitative accuracy is higher in DRS than in PAS. Details of this work are given below."

Mar 1, 1992

By R. L. Schmidt

The Methane Control and the Respirable Dust Groups at the Twin Cities Mining Research Center (TCMRC) cooperated recently in obtaining production samples of approximately 1 ton each, from the loading conveyors of a ripper, a borer, and a loading machine in conventional development headings. These samples were sized, in four stages, from plus 4 in to minus 10 µm. The conventional product had the least fines of the three production methods. The borer product had more fines than did the ripper product, but it also had a greater amount of large pieces. All three products, as sampled, had essentially the same amount of minus 10-µm particles. Photomicrographs and surface?-area comparisons were made. Gas -adsorption, surface-area determinations on particles under 37 µm give essentially the same value. Surface-area calculations, assuming spherical particles and no porosity, give a smaller area to the conventional product.

Jan 1, 1972

By K. A. Johnson, H. F. Yancey

"INTRODUCTION Coals vary so widely in their burning characteristics that all coals prepared for domestic stoker use cannot be burned efficiently on every type of stoker. The overfeed stoker, a large number of which are in use in the Pacific Northwest, operates satisfactorily when burning low- to high-ash, noncaking bituminous or subbituminous coals, whereas on the clinkering-type, underfeed, bituminous stoker both caking and noncaking bituminous and subbituminous coals are burned, generally with ash contents below 12 percent and ash-softening temperatures between 1,800º and about 2,600º F. Because fly ash continues to be one of the most troublesome factors in domestic underfeed stokers, noncaking coals especially must be chosen carefully with respect to size composition, particularly as regards the exclusion of excessive fines. Their formation as a result of degradation in storage handling or because of crushing in .the stoker worm will increase the fly-ash nuisence.Bituminous and subbituminous coals with higher ash-softening temperatures and, often, higher ash contents have not been able to enter the domestic stoker-coal market in the Pacific northwest because clinkers are not formed readily during clinker-type underfeed-stoker burning, especially in mild weather, and because of the labor and attendant inconvenience required in handling larger volumes of ash. The work described in this report was undertaken to enable mines producing coals of the kind described to enter the stoker-coal markets. The anthracite stoker selected was one that conveys the refuse from the ash pit of the furnace and deposits it into one of two covered, dust-tight disposal cans."

Dec 1, 1945

By D. E. Redmon

Linear programing provides a mathematical technique by which activities can be planned in such a way that an optimal result is obtained. Routine applications of linear programing require only a knowledge of algebra. However, a complete understanding of the fundamentals of linear programing requires a knowledge of advanced mathematics. The purpose of this publication is clarification of terminology and illustration of applications in comparatively simple mining problems. Two mining situations are considered: Mine stopes from which ore is to be produced at a minimum production cost; also, uranium mines from which ore is transported to one mill, a maximum monetary value is desired. The details of data arrangement for solution by linear programing are described and the solutions are presented. Results of these solutions indicate successful applications of linear programing to mine production scheduling.

Jan 1, 1964

By Robert E. Barieau

This report describes a method for treating pressure-volume-temperature (PVT) data obtained with a Burnett compressibility apparatus. The method makes use of a general nonlinear least-squares technique developed at the Bureau of Mines Helium Research Center. It is assumed that an adequate functional form is available for the expression of the compressibility factor as a function of either the molal density or the pressure. The functional form of the compressibility factor can be either linear or nonlinear in the parameters to be evaluated. Formulas are given for calculating variances and covariances of all parameters evaluated and for calculating the variance of calculated quantities of interest.

Jan 1, 1967

By A. G. Galaitsis

The two volumes of this report summarize the noise control work performed by BBN on a rail personnel carrier operated in coal mines. Volume I of the report - submitted November 1977 - describes the aboveground work performed to identify the noise sources, design, fabricate, and install the treatments, and evaluate the treatments through noise and vibration tests. The current volume (II)-describes the underground work conducted by BBN to determine the deterioration, if any, of the treatments when the vehicle is operated normally in a mine. There were no significant changes in the acoustical performance or mechanical integrity of the treatments at the end of a three-month period.

Jan 1, 1980

This document is Volume II of a two-volume report on underground and surface coal mine fires occurring between 1950 and 1977. Volume I discusses the methods of data acquisition, data analysis procedures, results and conclusions. This volume contains (1) a master list of all fire incidents obtained from MSHA reports, (2) an annotated bibliography of all MSHA reports, journal articles on selected incidents, and non-reportable fires (appendix), and (3) indexes to be used in accessing incidents in the master list and annotated bibliography. These three types of information provide the reader with a complete summary of coal mine fires during the period from 1950 through 1977 and a convenient means to locate incidents of specific interest. The body of this volume is organized around two tables and a series of indexes. The two tables are master lists of underground and surface fire incidents. They are followed by 14 indexes keyed to the master list and annotated bibliography. The appendix contains three different parts: o The annotated bibliography of MSHA fire reports (one section each for underground and surface mine fires) o The annotated bibliography of journal articles about selected fires from the MSHA bibliography o A listing of non-reportable fires (one section each for underground and surface mine fires) Descriptions of the contents and use of each of the three major components of this volume (i.e., master list, indexes, and appendix) are presented in Section 2.0.

Jan 1, 1979

By B. Gillenwater

This report describes the results of investigations into four specific areas related to trolley wire power distribution systems in coal mines. These are: 1. Partially insulated (shielded) trolley wire 2. High-speed insulator fault detectors 3. Dual-wire trolley systems 4. Insulator failure indicators. Prototype devices or designs were developed in each area. In addition, a brief survey was made in an attempt to assess the Future of mine trolley systems, and data was collected and reviewed in an attempt to analyze the nature of trolley wire related accidents. Other options for decreasing the risks associated with trolley systems that arose .during the study are briefly described in appendices. These include insulating equipment and miners from return and/or energized conductors and use of a segmented trolley wire with local control of current delivering capability.

Jan 1, 1981

By D. A. Hill

This volume contains a summary of the results of past analyses on U.S. Bureau of Mines Contract No. H0122061 which are relevant to electromagnetic location in mine rescue situations. The analytical results indicated that detection of a trapped miner equipped with a special transmitter is feasible in most situations. Location of the miner by surface measurements is also generally feasible within certain errors. The feasibility of miner detection and the accuracy of miner location have been examined theoretically for a wide variety of situations. Agreement with experimental results is generally good in cases where measurements are available.

By L. B. Pankratz

Thermodynamic data on the sulfides were reviewed, evaluated, and compiled at the Bureau of Mines Albany Research Center. Values for Cp°, S°, H°298 -(G° - H°298)/T, ?Hf°, ?Gf°, and log Kf are given in tabular form. Cp°, H° - H°298, ?Hf°, and ?Gf° are also expressed algebraically.

Jan 1, 1987

By John P. Shubilla1, Nicholas Kyriazi

A joint effort by the Pittsburgh Research Center (PRC) and the Mine Safety and Health Administration (MSHA)3was undertaken to determine how well self-contained self-rescuers (SCSR's), deployed in accordance with Federal regulations (30 CFR 75.1714), held up in the underground environment with regard to both physical damage and aging. This report presents findings regarding laboratory-tested SCSR's in the fifth phase of testing from mid-1993to early 1996. The SCSR's were tested on human subjects and on a breathing and metabolic simulator (BMS) at PRC. These results indicate that most of the apparatus, if they pass their inspection criteria, perform satisfactorily.

Jan 4, 1996

By T. L. Muldoon

The bagging of dry pulverized products using fluidized air packers creates severe respirable dust problems in many surface mining operations. During bag filling, excess air and product blows by the bag valve/nozzle interface. After bag ejection, dust blows out of the bag valve. During conveying and handling dust is released from the bag valve and dirty bag surface. Overexposure of the bagging machine operator and bag handlers is common. This report describes the development and testing of a new dust control system for bagging machines. The system features a new bag clamp design to reduce product blowby during filling. A controlled vacuum system removes excess air from the bag before ejection, eliminating the problems after bag ejection and during conveying and handling. The system has shown significant reductions in dust exposure for both bag machine operators and bag handlers. These reductions are achieved with no significant effect on total mill productivity.

Jan 1, 1985

By Michael D. Balen

This Bureau of Mines open file report is one in a series of reports written about the Valdez Creek Mining District (VCM D) as a result of the continuing Bureau of Mines mining district evaluation program. This report presents the results of order-of-magnitude mining feasibility studies. The mining feasibility studies were conducted for mineral deposit models that were based on real and hypothetical deposits that occur in the VCMD. A total of 6b mine models were developed for application to the mineral deposit models. The goal of the feasibility study was to determine the monetary value per unit of minable ore that would cause the simulated cash flow for each of 66 mine models to achieve certain pre-defined rates of return for the invested capital.

Jan 1, 2011

By Alexander May

The Bureau of Mines conducted studies to determine if phosphogypsum, a waste material from the processing of phosphate rock, contains hazardous toxic materials as defined by the Environmental Protection Agency (EPA) and whether leaching of these toxic materials and radium may occur. Samples of the phosphogypsum stockpiled material were evaluated using the EPA extraction procedure, atomic absorption, neutron activation, x-ray diffraction, and chemical and physical means. Radiological tests performed used both the germanium-lithium and emanation methods. The data show that the phosphogypsum stockpiles are not hazardous toxic waste as defined by EPA criteria. Trace elements and radium are not leached from the phosphogypsum stockpiles. Absorption of trace elements and radium by phosphogypsum is the major reason for their not being leached. The standard error of measurement of radium concentrations was 4.7 pCi/g.

Jan 1, 1983

By Claude W. Sill

In the usual volumetric determination of uranium, the solution containing uranium is reduced in a Jones reductor, yielding a mixture of trivalent and tetravalent uranium; the trivalent uranium is oxidized to the tetravalent state by bubbling a stream of air through the solution. The resulting solution of. Tetravalent uranium is titrated with a standard oxidant, generally sulfatoceric acid, dichromate, or permanganate; It seemed likely that the, same general procedure could be used in determining semimicro quantities of uranium if the conditions affecting the variables involved were understood more clearly than at present. In the method described below, the use of ferric sulfate to oxidize tetravalent uranium allows the titration to be made at room temperature in an essentially colorless solution with sulfatoceric acid. The latter oxidant its turn permits the use of the very stable indicator, ferroin, with its sharp color.., change and exactly reproducible blanks. Solutions of uranyl sulfate were prepared by diluting a stock solution that had been standardized gravimetrically according to the method of Lundell and Knowles (8).3/ Solutions of sulfatoceric acid were prepared according to the directions of G. F. Smith (12) and were standardized against arsenic trioxide in the presence of osmic acid according to the directions of Gleu. The cerium solutions were stored in 18-liter carboys fitted with siphon arrangements so that the bottles did not need to be opened and protected from light in a dark cupboard. Under these conditions, even the 0.01 N solution changed by less than 1 part per thousand over a period of about 6 months.

Jan 1, 1952

By Laurence G. Trudell

Geology and oil-yield data are presented for a 58-square-mile area encompassing the U.S. Department of the Interior oil-shale leasing program tracts in the western Washakie Basin, Sweetwater County, Wyo. Lithology and oil yields of samples from three Bureau of Mines coreholes are evaluated and correlated with Kinney Rim surface sections measured and sampled by the U.S. Geological Survey. Minable sections of oil shale averaging up to 25 gallons of oil per ton crop out on Kinney Rim in the Laney Member of the Green River Formation. Thick oil-shale sections in the Laney Member that average 15 gallons per ton represent 155 million barrels of oil in place per square mile. In the lower part of the Green River Formation the Tipton Shale Member contains a 20-to 40-foot section averaging 15 gallons per ton. Beds of high-volatile C bituminous coal up to 6 feet thick are present in intertongued parts of the lower Green River Formation and upper Wasatch Formation.

Jan 1, 1973