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By R. V. Ramani

This report is volume 2 of an eleven-volume final report for a Grant completed by The Pennsylvania State University for the Bureau of Mines to develop a dynamic general purpose computer simulation model for underground coal mining. The simulator developed under the Grant has a wide range of possible applications in the design and evaluation of underground coal mining systems from the standpoints of health and safety, productivity, and mine environment. The Master Design Simulator consists of nine free-standing function-oriented subsystem models linked together into an integrated, comprehensive model of an entire mining system. The subsystems comprising the Master Design Simulator include geology and reserves, methane generation, roof support, subsidence, production, rail haulage, cost, water generation, and ventilation. This volume of the final report describes the Geology and Reserves subsystem of the Master Design Simulator. The two functions of this subsystem are: 1) the design of a geological data library to provide input to the other subsystems of the simulator; and 2) the calculation of coal reserves and associated values and grades under various user-specified conditions. The subsystem uses a weighted moving average method to interpolate between the borehole values, and provides output in report format, graphical plots and/or storage on magnetic tape or other storage devices for later retrieval. The application of the subsystem as an independent model with test results and comparisons with other methods of computing reserves is also presented. The appendix comprises a users manual for the model, and includes a program listing.

Jan 1, 1974

By C. A. Taylor, C. E. Munroe

"In blasting the explosion of the high explosives charge is initiated by means of a detonator. Consequently the successful operation of the whole system is, ab initio dependent upon the suitability and efficiency of the detonator used. A considerable number of methods for testing the efficiency of detonators have been devised. In a previous publication*** of the Bureau of Mines many of these were discussed after having been classified as direct and indirect methods.In 1910, W. O, Snelling, then explosives chemist of the Bureau, devised a direct method which depends on the extent to which a hard brittle material of uniform granulation, such as quartz sand, is pulverized by the explosion of the detonator when imbedded in it, and, as a container in which to carry out the tests, he devised the vessel known as the Bureau of Mines sand-test bomb No. 1. A brief mention of his work was made in a paper presented to the Engineers' Society of Western Pennsylvania.****Later Storm and Cope made a very extended investigation of this method using sand-test bomb No, 1. Their paper***** contains a detailed, illustrated, description of sand-test bomb No. 1, with precise specifications of the sand and a minute account of the technique followed, together with a discussion of the data they obtained from the tests in this bomb of 112 detonators representing each of the grades from We, 3 to No. 10, inclusive. The average of results obtained by them are set forth in the following table."

Dec 1, 1923

By Louis C. Brichta

"The O'Jack Mining Co.'s zinc and lead deposits in Jasper County, Missouri, have been worked intermittently since the early nineties; production from these deposits was greatest during World War I and II - 4,668 tons of zinc and lead concentrates. The deposits are in a sink-hole structure in which intense deformation has taken place and in areas of disturbance in the sheet-ground horizon.While high-grade ore was being mined, the operators sank seven churn-drill holes for the purpose of extending reserves. They then asked the Bureau of Mines to explore the deposit with the object of developing a reserve of lower-grade ore that could be mined by open-pit methods. Twenty-two holes were sunk. The methods of drilling and sampling and the logs of the holes, as of those drilled by the operators, are given later in this report.INTRODUCTION AND ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mined has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts development by each exploratory project as soon as practicable after its conclusion. Preliminary examination, conduct of exploratory work, and preparation of final reports are functions of the Mining Branch, Lowell B. Moon, chief, under the supervision of Dr. R. S. Dean, assistant director."

Nov 1, 1946

By Fun-Den Wang

This report presents theoretical studies and experimental work dealing with the detection of dangerous roof and pillar conditions in underground mines through measure¬ment of temperature differences on the surface of the mine opening. The theoretical work is directed at modeling the circumstances where a loose slab of rock might be detected. The experimental work provides input data for the theoretical models. At the beginning of the project, little was known by the authors of the conditions that would permit detection of a loose slab of rock or coal by measuring the surface temperature differences. The U.S. Bureau of Mines had found that there were detectable surface temperature differences on the roofs and pillars of mines. The Bureau contracted with Colorado School of Mines to measure temperature profiles around mine openings in an effort to learn if the temperature differences they had detected were directly related to loose pieces of roof and pillar rock. The Bureau was principally interested in learning if loose rock could be found in coal mines by measurement of surface temperature differences with an infrared thermometer.

Jan 1, 1972

By John C. Cook

Channel sand bodies ("wants" or "cutouts") are deposits of barren, hard sediments which interrupt production and pose safety hazards when encountered in underground coal mining. To locate these costly impediments to mining in advance, from the surface of the ground, the seismic reflection method is recommended. High-resolution (high frequency) techniques for shallow seismic exploration of coal beds have been worked out and are reported here, including a field example. Newly-developed high-frequency, digital recording equipment was used, together with light-weight shot-drilling equipment and a variety of down-hole seismic impulse sources. Techniques for rapid but complete coverage of a coal prospect area with a crew of 2 to 6 men n 2 or 3 vehicles are described in detail.

Jan 1, 1976

By M. J. Ackerman

This study was undertaken to make a comparison between the cost of mining coal under roof bolt and under conventional timber methods of roof support. Studies were made at 14 mines in Pennsylvania, eastern Ohio, and northern and southern West Virginia. At each mine data were obtained for sections of the mine where the physical conditions, mining equipment, and mining systems were similar. Coal, recognized as one of the basic industrial fuels, is very competitive with other fuels, and management, in order to protect and enlarge its market, must be continually alert to find more efficient methods of production. Continuous production of coal is desired by all operators but never obtained. In mechanized mining the performance and production vary with operating time, which can be interrupted by many variable factors, such as condition of the roof, method of roof support, condition of equipment, water, ventilation, power, transportation, efficiency of operating crew, and supervision.

Jan 1, 1961

By Lloyd Williams, R. E. Hershey, B. W. Gandrud

"1. The investigation shows that the Sewanee bed is the only bed of major importance in Marion County, 97 percent of the coal mined in the county having come :from this bed. There are coal reserves in minor quantity in the Battle Creek bed, and production from this bed depends on a few small truck mines. The Richland bed, or Lower Sevanee has been mined in the past, but no coal has been produced from it in late years. There are no production records of any other beds in the county, although some coal has been produced from them.2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and on l,800 tons per acre-foot of coal in place, are estimated to be 61 million short tons as of January 1, 1953. Of this total, 55 million short tons is in beds 28 inches and more thick. Areas in each bed ·were omitted from the estimate where available data relative to the bed characteristics are too meager to permit making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.3. Recoverable reserves of coal are estimated in beds 28 inches and more 'thick. This recovery is based on total thickness of coal in the bed (less partings 3/8-inch thick or more), rather than on the thickness of the coal actually mined. This thickness is about the minimum now being mined by hand loading onto conveyors in the Appalachian Region. The combined weighted average recovery for the Sewanee and Battle Creek beds in Marion County, as determined by this investigation, is 60.9 percent. Based on this, the recoverable reserves of coal in Marion County are estimated at 34 million tons."

Oct 1, 1955

By J. C. Dumbrille

The following account of wining practices of the Kirkland Late Gold twining Co., (Ltd.), at Kirkland Lake, Ontario, is one of 4 series of papers being prepared by the United States Bureau of Mines on mining practices, methods, sad costs in various districts. The author has prepared this paper with the help and permission of J. B. Tyrrell and W. M. Sixt, the managing director and the mine manager, respectively. This mine is operating at a daily rate of about 150 tons.

Jan 1, 1931

By R. H. Bedford

"The El Dorado copper mine is situated in the foothill copper-zinc belt of California, which traverses the western slope of the Sierra Nevada with unusual persistence from Butte County to Kern County, a distance of more than 300 miles. Although this area contains such important past producers as the Penn mine, Union, and others, a great part of the current production has been derived from smaller properties, which depend largely on premium metal prices for economical operation. The El Dorado mine is in the latter group, which constitutes an important source of metal in a national emergency.Exploration by the Bureau of Mines by means of eight diamond-drill holes Indicated narrow, intermittent lenses of copper ore along structures boo feet in length. The copper occurs in massive sulfides composed of chalcopyrite, pyrite, pyrrhotite, and minor quantities of bernite. The sulfides have evidently replaced tuffs, which are interbedded with the Mariposa slates and shales.H. A. Weiler and Hal T. Hall, owners of the El Dorado copper property, requested an examination by the Bureau during the latter part of 1914. In December of that year an engineer of the Bureau of Mines visited the mine and recommended the project work undertaken. The purpose was to aid the owners in bringing the property into production of copper and zinc, which at that time was critically essential to the war industries.Complete factual data obtained by the exploration are embodied in this report.In its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G, Knickerbocker, chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director.Acknowledgment is made to A. O. Johnson, chief, Reno Division, Mining Branch, and Lowell B. Moon, chief, Mining Branch, for their aid and direction."

Jun 1, 1946

By S. H. Ash

The Pennsylvania anthracite region is composed of four fields, namely, the Northern, Eastern Middle, Western Middle, and Southern. It is in the eastern part of Pennsylvania and is shown on figure 1. The anthracite industry is confronted with a crucial problem of inundation by water impounded in underground pools in many mines and by infiltration of water from streams and pools on the surface (3). The deposits of anthracite in the United States are limited virtually to Pennsylvania, and the difficulties of this industry have been commonly considered as a State problem rather than a national one (1, 4, 6, 7). Anthracite was discovered in Pennsylvania in 1762, and the first mining company was formed in 1793. It was not until 1812 that anthracite began to receive recognition in the Philadelphia market as a domestic fuel, and by 1838 the annual production was nearly 1 million net tons. Since anthracite mining began, mine water has become progressively more difficult and costly to handle because of the extraction of anthracite both underground and along the outcrops of the beds, until at the present time mine drainage is a major anthracite-mining problem. Mine water is handled at the anthracite mines as follows: (a) by pumping, (b) by drainage tunnels, (c) by combination of pumping and drainage tunnels, and (d) by water hoists (hoisting water by means of large buckets) (4, 5,6, 7). This paper covers removal of the water from mines by means of pumping plants. Pumping is indispensable in the production of anthracite (5). The cost of pumping mine water has increased progressively since anthracite mining began. Some collieries have been forced to discontinue mining because of the high cost of pumping.

Jan 1, 1950

This manual provides instructions for installing, operating, and maintaining a protective canopy on the Joy Mfg. Co. loader. These instructions are based upon two actual install .at ions: one made in a mine on loader, model 14BU10-11AH, and one in the factory on model 14BU10- 11AH. The parts list and engineering drawings for the protective canopy are included at the end of the manual. And a discussion of some alternative design concepts is also included. The manual can also be used for retrofitting other loaders with similar protective canopies. Skilled mechanics can determine if the instructions herein would be applicable to the other loaders and can determine any necessary modifications if they are not.

Jan 1, 1973

By J. F. McIlwain

The Bureau of Mines has investigated fumes generated by selected welding electrodes used in mines in order to help determine their relative health hazard potential. Fumes were generated and collected in an enclosed chamber for subsequent generation rate and chemical constituent determination. Shielded metal arc electrodes from the following groups were tested: AWS types E308-16 and E310-16 stainless steel, ECoCr-A Co-Cr hardfacing alloy, ENiCr Ni, an Mn-Cr buildup alloy, E7018 carbon steel, and EII018-M low-alloy steel. Flux-cored wire electrodes of this last group also were tested. Fume generation rates and the chemical composition of the fumes were measured. From these data, exposure in-dices were determined, which give a relative measure of the health hazard potential of using the electrodes. The effect of welding onto build-up alloy layers on the fume composition also was examined for five of the higher alloy groups.

Jan 1, 1987

By Clayton M. Rumsey

No producing or developing mines nor known mineral resources are in the Lower Saline Valley Wilderness Study Area. The inactive Bonanza Prospect has low potential for copper-gold-silver resources. Stone and sand and gravel deposits in the WSA do not constitute mineral resources because transportation costs to major markets are prohibitive. INTRODUCTION The Lower Saline Valley Wilderness Study Area (WSA) covers 2,241 acres in southeast California adjacent to and west of Death Valley National Monument (fig. 1). Access to the WSA is by the Saline Valley gravel road 28 mi northerly from its junction with State Highway 190. The junction is about 35 mi southeast of Lone Pine, CA. The WSA is characterized by moderate to steep, sparsely-vegetated slopes; elevation ranges from about 1,800 ft to 3,560 ft.

Jan 1, 1984

By Stephen A. Swan

This Bureau of Mines report discusses research to analyze and evaluate extended bumper systems in order to determine the degree of protection provided to equipment operators in the event of rear-end collisions be-tween off-road rear-dump haulage trucks. The basic characteristics of rear-end collisions were determined, and a detailed analysis of the col-lision dynamics was performed to identify the magnitude and direction of impact loads, the amount of energy that must be absorbed during impact, and the major factors that affect the outcome of a collision. Separate bumper designs were developed to facilitate attachment to four 170-st-capacity haulage truck frame types.

Jan 1, 1987

By Eugene T. Sheridan

The Bureau of Mines annually canvasses the peat producers in the United states and publishes economic data on the peat industry, based upon reports submitted by producers. This publication lists all producers that reported commercial production to the Bureau for 1960 and presents data on individual plants. The companies named herein represent virtually all commercial producers, although a few small companies may not have been canvassed as the industry has many small operations that operate intermittently. Output of the various companies listed ranged from a few tons to more than 50,000 tons. Peat is included in the Bureau's annual surveys of the mineral industries because peat is classified as a mineral fuel. Although none is used for fuel in the United States, peat is a potential source of energy and ranks as one of our large mineral resources. The domestic peat industry sells peat, chiefly, for use as a soil amendment for general soil-improvement purposes. During the past decade the industry has expanded rapidly with operations increasing from 45 in 1947-494/ to 115 in 1960. Output during this period has more than tripled, increasing from 131,782 short tons to 470,889 short tons.

Jan 1, 1961

Provide an unobstructive means of measuring small changes in distance from roof to floor or from rib to rib of a mine opening and the rate of closure in order to help operators of under-ground mines detect hazardous ground conditions. Approach A small ultrasonic measurement system was developed to detect g round movement and define closure rates. How the System Works The system contains two parts: a transducer and a readout device. The small ultrasonic transducer, similar to an audio speaker diaphram, is plucked with an ultrasonic frequency every six seconds. This frequency wave is sent through the air and reflected back to the transducer off any surface at which the transducer is pointed. The amount of time needed by the ultrasonic wave to make this round trip is accurately measured using a precise oscillator / timer and is converted into a measure of distance. The accurate 6-second time interval is used to convert any subsequent changes in the reading to a rate of change in feet per minute. Two readings are then displayed alternately on the readout instrument.

Jan 1, 1984

By M. G. Zabetakis, T. D. Moore

The use of a partially slotted 6.5-inch-inside-diameter vertical pipe to remove methane from a longwall gob area at a depth of 2,260 feet in the Pocahontas No. 3 coalbed ms investigated. The value of gas removed by such a pipe under free-flow conditions was found to equal the cost of the installation in this case. Approximately 25 percent of the available methane passed through the pipe without the use of an exhauster; an additional 10 percent was removed when an exhauster was employed. The diversion of methane through a vertical slotted pipe to the surface permitted the use of increased mining rates and decreased the ventilation air requirements.

Jan 1, 1972

To allow the controlled yielding of mine walls in order to reduce rock-burst hazards and reduce maintenance caused by excessive squeezing forces. Approach Rock bolts that elongate and continue to sustain a load, have been fabricated and tested. This device is an adoption of a concept originally developed in South Africa for use where unusually adverse conditions may warrant the added cost. How It Works A coupling in the rock bolt allows controlled elongation if the load increases beyond the bolt's design strength. (The load can build up either slowly, as during heaving, or rapidly, as before a rock burst.) The elon¬gation of one or more rock bolts surrounding a mine opening, allows the rock to move from its original position to c new position in a controlled manner. This movement relieves the rock stresses, and the mine opening reaches a new state of equilibrium. The elongatible coupling of the rock bolt consists of a

Jan 1, 1977

By Lloyd Williams, H. K. Gibbs, William L. Crentz, J. W. Miller

"Reserves This investigation shows that the Poplar Creek is the most important bed in Scott County from a production standpoint. Although the Poplar Creek bed contains the largest reserve, the Big Mary has a larger recoverable reserve. Estimates of reserves also have been made for the Pewee, Red Ash, Windrock, Upper Pioneer, Jellico, and White Oak beds.Known measured and indicated reserves of coal, based on a minimum bed thickness of 14 inches and on 1,800 short tons per acre-foot of coal in place, are estimated to be 143 million tons as of January 1, 1954. Of this total, 74 million tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics are too meager for making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.Recoverable reserves of coal are estimated in beds 28 inches and more thick. This thickness is about the minimum now being mined by hand loading onto conveyors in the Appalachian region. The weighted average recovery for all beds in Scott County, as determined by this investigation, is 52.4 percent. This percentage is based on the total thickness of coal in the bed (less partings three-eighths inch or more thick) rather than on the thickness of the coal mined. Based on the weighted average percentage of recovery for all beds in Scott County, the recoverable reserves of coal are estimated to be 39 million tons as of January 1, 1954.Coal Analyses Chemical analyses of coal samples taken for this study show that the coal in Scott County is of high-volatile a bituminous rank except the Upper Pioneer bed, which is shown to be high-volatile B bituminous. The Pewee bed shows typical low-sulfur characteristics. The high ash and sulfur in the Big Mary are characteristic of that bed. The Poplar Creek is moderately low in ash and sulfur in areas where there is no parting in the bed."

Jun 1, 1956

By F. Keith Shelton

"INTRODUCTION Cobalt is an essential metal in the normal industrial ac¬tivity of the United States. Being an important constituent of high-speed steels and other cutting-tool materials, it becomes of critically essential importance during periods of national emergency. 3/ The Presidential order of December 20, 1940, included cobalt among other essential commodities that could be exported only under license. The Executive order 4/ listed cobalt metal, cobalt oxide, and alloys containing more than 5 per¬cent cobalt as being within the licensing requirements.There was no domestic marketed production of, cobalt products from 1931 until 1940 when the Pyrites Co. 5/ produced some cobalt oxide. The major portion of the domestic cobalt requirements has been obtained from Northern Rhodesia, the Belgian Congo, and French Morocco. 6/ The uncertainty of sea transportation from those sources of supply demanded that steps be taken to obtain from domestic raw materials an adequate supply of cobalt for use in the materials required for production of indispensable machined war metal products. In connection with the national policy for attaining self-sufficiency of strategic and critical materials, the Bureau of Mines, Boulder City, Nev., Experiment Station initiated studies to recover cobalt from the low-grade oxidized cobalt deposits in the Goodsprings district, Nevada. Hewett 7/ reported occurrence of cobalt specifically in the Blue Jay, Columbia, Copper Chief, and Highline mines and generally over a widespread area in the district."

Jan 1, 1946