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Coal has been mined in the central Appalachian coalfields of southern West Virginia, western Virginia, and eastern Kentucky for more than a century. The dwindling reserve base consists in large part of coal that would have been considered unmineable by earlier generations. Nearly every current operation is working on a property where coal has been extracted in the past, from seams either above, below, or both. NIOSH is conducting research aimed at helping mine planners prevent hazardous conditions due to multiple seam interactions. To-date, more than 300 case histories have been collected from underground mines, mainly from central Appalachia. This paper focuses on several of the more challenging situations that have been encountered, including: • Room-and-pillar development 20 ft (6 m) beneath full extraction workings at a depth of 1,000 ft (300m) of cover (Virginia) • Pillar recovery 45 ft above full extraction workings at 900 ft (270 m) of cover (Virginia) • Near-simultaneous room-and-pillar mining with pillar recovery with 40 ft (12 m) of interburden and 1,500-2,000 ft (450-600 m) of cover (Kentucky) • Longwall mining directly beneath main entries in overlying seams (West Virginia) • Some of these operations have been highly successful in overcoming the challenges, others less so. The lessons learned from their experience will help ensure that these and similar difficult reserves can be mined safely.

By Oliver Bowles

"Simple systematic accounting that adequately records all transactions has long been regarded as essential to the welfare of any business enterprise. Some of the defects that detract from the prosperity of the slate industry are attributable to a lack of effectiveness in cost keeping. This condition has prompted the United States Bureau of Mines to make a detailed study of accounting methods for the slate industry, and to present for consideration a system of accounts, which it is believed would enable the industry to attain more economical management and operation if accepted by a fair proportion of its important units.The method of accounting presented herein has been worked out with the assistance of leading slate producers and the recommendation are tentative and are submitted in this form as a means of developing constructive criticism. Believing that cooperative effort in this, as in many other problems, will bring the most enduring benefits to the industry as a whole, the writer urges that the most earnest consideration be given to this vital problem now facing the slate industry.Grateful acknowledgment is made of the helpful assistance rendered by R. E. Eckert of the accounting firm of Eckert, Degan, and Palmer of Easton, Pa., in compiling the charts and the explanatory text. He has brought to this work a wide knowledge of accountancy, supplemented by a background of direct contact with the slate industry, and his presence at the various conferences has been of great advantage in clearing up difficulties. The National Slate Association sponsored the cost study and chiefly through the efforts of President W. H. Smith and Secretary W. S. Hays, has aided greatly in conducting it. Acknowledgment is also made of assistance rendered by William F. Marsh of the United States Bureau of Mines."

Nov 1, 1929

This: symposium was sponsored by the Bureau of Mines, U.S. Department of the lnterior, in order to critically examine the state-of-the-art of sulfide flotation chemistry and to define current and emerging problems that should be emphasized in future fundamental research. The topics covered through invited papers include both reviews and recent research results in the areas of thermodynamics of reagent-mineral interactions; collector adsorption processes; the effects of solid-state point defects on flotation; activation and deactivation phenomena; the electrochemical role of oxygen in sulfide flotation; environmental problems in flotation; and selective flocculation of fines. Papers riving perspectives on flotation research in relationship to our national mineral requirements and the relationships between industrial flotation research and academics are also presented. An edited summary of the symposium follows the papers.

Jan 1, 1980

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 Bruce I. Thomas

[THIS PAPER, tine of a series on placer ml n in iii Alaska, describes mining methods and gives unit costs at operations where hydraulic and mechanical excavation equipment is used with nonfloating washing plants. The mining methods described were developed during the last 30 years to copy with conditions peculiar to arctic and subarctic regions arid are now used by a large segment of the placer mining industry in Alaska. The operations described have been classified if m ii into three main categories: Those having sluices at a bedrock level, those having sluices above bedrock and those having mobile nonfloating washing plants (dryland dredges). Diesel-powered bulldozers and draglines convey or clevate gold-bearing gravel to the sluices, remove tailings, and strip waste gravel and other overburden. Diesel-powered centrifugal pumps supply water foe sluicing and hydraulic stripping. Detailed descriptions and unit cost arc presented for 14 operations to illustrate the numerous arrangements udder the first 2 categories.]

Jan 1, 1959

By Douglas Ketcham, Thomas Jetzer

While the neurological and vascular aspects of Hand-Arm Vibration Syndrome (HAVS) has been generally accepted as a medical condition, the medical criteria and the clinical findings used to establish the diagnosis has been more difficult to bring to consensus. The criteria was first quantified by the Taylor-Palmear scale.1 This criteria was subsequently modified in 1986 at the 1st Stockholm Workshop2,3 to included more acceptance for the neurological effects that characterized the predominate findings in some workers. The relationship between hand-arm vibration and Carpal Tunnel Syndrome was defined in NIOSH 97-1414. While the aforementioned documents have defined the clinical entities associated with hand-arm vibration exposure, agreement on the clinical findings and test to confirm the diagnosis has be been more difficult to bring to consensus. Clinicians assessing HAVS has relied on a number of varied neurological and vascular tests. The neurological testing has focused on assessing damage to the sensory capability of the fingers for the neurological component including tests to measuring ability to sense vibration, cold or other end point finger sensor functions. However, the vascular testing has been traditionally focused on the ability to either measure vascular function or to reproduce the vascular blanching that occurs in HAVS with cold water provocation. Recent assessment of this testing in the United Kingdom Coal Miner’s study has questioned the value of this testing especially in reviews by McGeoch.5 In an attempt to provide some type of definitive testing to substantiate vascular damage from hand-arm vibration exposure, angiography is an alternative or adjunct to cold water provocation testing. The standards that have been established to predict the level, type and incidence of HAVS have been based on clinical studies and reports that have essentially been all male populations. However, the recent entry of women into more vibration intensive jobs has brought about the exposure of some women to high levels of vibration previously only previously experienced by men. However, there have been only few studies that look at HAVS in women6. Although exposed the same vibration levels, it has not been clear that the latency and type of pathology of HAVS in women will be the same as for men. The purpose of this study is to look at recent case studies of men and women exposed to jobs with high levels of hand-arm vibration with extensive clinical testing for both the neurological and vascular components of HAVS as well as other associated upper extremity conditions such as Carpal Tunnel Syndrome.

Jan 6, 2006

By Mark S. Sanders

This report presents recommended visibility requirements for continuous miner, shuttle car and scoop operations and details the methodology used to generate them. A task analytic approach was used to define information requirements and visual features which served as sources of information. Information requirements were prioritized and the location of visual features determined. From this analysis, visual attention locations, containing one or more important visual features, were identified. A total of 71 locations-were identified for continuous miners, 54 for shuttle-cars and 54 for scoops. A procedure was developed for assessing whether operators in existing machines could be expected to see the visual attention locations. The procedure makes use of a Human Eye Reference Measurement Instrument (HERMI) designed for this project and an outside-in photographic procedure for documenting compliance with the recommendations. A sample of continuous miners, shuttle cars, and scoops were used to test the procedure. Results are presented in the report.

Jan 1, 1981

By D. J. Dollhopf

This research was part of an effort to investigate means of reestablishing non¬polluted hydrological systems in areas where surface mining directly impacts shallow ground-water resources. Chemically undesirable overburden material was selectively backfilled with the intent that it would be below the future root zone, be above the reestablished aquifer, and would not be leached as a result of deep percolation. After 2 years the buried material remains above the spoil aquifer and below the maximum rooting depth. Unsaturated water flow from the land surface to the buried material occurred during wet climatological periods. No significant leaching of buried material was observed, however. Overburden sample contamination from drill stem joint grease with Pb, Zn, and Cu additives caused substantial error regarding DTPA extractable trace metals. A grease with teflon and talc additives was recommended for use in future sampling programs. DTPA extractable trace elements in overburden material had no statistical relationship to post-mine ground-water quality. Overburden columns leached with water produced leachates comparable to overburden and spoil ground-water trace metal quality. A depositional model described the Rosebud Coal overburden as a fluvial system with distinct units of sand, silt, and clay, with distinct chemical properties. Physical and chemical characteristics of the model were comparable to the in situ geochemical system, a relationship which may aid in locating overburden materials unsuitable for reclamation.

Jan 1, 1979

By John H. Johnson

A study of mine air quality was conducted using the latest advanced continuous monitoring instruments. An overview of the various interacting variables in the mine that affect air quality is presented. One effort involves the evaluation of portable instruments, the development of measurement techniques, sample analysis procedures and computer programs for statistical analysis of measurement data, and the application of the instruments and techniques to the measurement of the concentrations of CO, CO2, NO, NO2 and particulate matter in a lead and a copper underground mine. A second effort involves the first application of the Mine Air Monitoring Laboratory (MAML), a mobile trailer containing laboratory type instruments, sampling and data systems for the measurement of CO, CO2, NO, NO2 and particulate matter. The data from the MAML for blasting and for operating diesel equipment are analyzed and presented in various plots.

Jan 1, 1977

The annual reports of the supervising engineers of the nine sections comprising the Mining Division are assembled here and constitute the annual report of the division. In planning activities the aim is to adapt them to changes in conditions, in the needs of the mining industries, and in the public interest: those that contribute most to solving the present problems are emphasized, investigations of less immediate importance being recessed if necessary.

Jan 1, 1941

The contract for the Water Jet Chock Mounted Miner Feasibility Study was awarded to FMC Corporation's Advanced Products Division on 18 November, 1974. The program was divided into four phases as follows: ? Phase I - Planning ? Phase II - Conceptual Design ? Phase III - Budgetary Cost Estimate and Economic Feasibility Study ? Phase IV - Final Report During Phase I, which lasted 1 month, most of the necessary information and data for the conduct of Phase II was obtained. To accomplish this, arrangements were made for personal visits to the University of Missouri at Rolla, Illinois Institute of Technology Research Institute, USBM TCMRC, Alpine Equipment Co., Mining Progress, Inc. and Eastern Associated Coal Corporation's Harris No. 1 Mine. Also, a list of manufacturers of high pressure equipment was compiled to be contacted during Phase II. Finally, the objectives to be accomplished during Phase II were outlined. The Phase I Report was submitted on 23 December, 1974. At the beginning of Phase II, personal visits were made to the research centers and firms mentioned above. Later an additional visit was made to the Harris Mine, and to the Pittsburgh Mining Research Center at Brucetun to observe a test of a water jet mounted on an Alpine Mining Machine. Equipment manufacturers of high pressure components such as hoses, tubing, valves, pumps, and intensifiers were contacted to obtain item performance data, availability, and cost.

Jan 1, 1975

By B. J. Dalton

The Bureau of Mines Helium Activity has developed a computer program for use in the reduction of pressure-volume-temperature (PVT) data obtained with a Burnett compressibility apparatus. This program includes important modifications and extensions of some of the methods currently used for treating these types of data and yields statistical information that cannot be obtained from any other published work. The methods of calculation make use of a general nonlinear least-squares technique developed at the Helium Research Center. Because of a need to investigate different functional forms for representing the compressibility factor isotherm, 2, the computer program has been written in such a way that the only additional coding required is the so-called compressibility function subroutine. This subroutine defines the analytical form of Z and certain of its partial derivatives. The program described herein is believed to be the most advantageous for use in treating isothermal Burnett compressibility data.

Jan 1, 1970

By Heithecker R. E.

In June 1933 the Bureau of Mines, in cooperation with the State of Oklahoma and the Oklahoma City Chamber of Commerce,, published a report of the gas reserves in the Oklahoma City oil field3/ based upon data as of October 1932, at which time there were 43 classified gas wells in the field, The estimates were obtained by the ?porosity-area" method. There are two general methods of estimating natural-gas reserves. The porosity-area method, as used by Hill and Rawlins, is used when a gas field is comparatively new but after enough drilling has been done to determine the average thickness, porosity, and areal extent of the producing horizon. The "pressure-volume? method of estimating gas reserves, the method used in this report, may be used after a sufficient volume of gas has bean withdrawn from the reservoir to cause an appreciable decline in reservoir pressure.

Jan 1, 1937

By Charles L. Kimbell

On the basis of world production data alone, 1985 appears to have been a year in which the world's mineral industry took another step upward in its recovery from the very poor years of 1981, 1982, and early 1983. Despite a drop in the output of crude oil, which was the single most significant crude mineral product from the viewpoint of value, the estimated value of world crude mineral production advanced by 3.4% to about $1,054 billion constant 1983 dollars, with output increases logged for nearly two-thirds of the commodities and forms of commodities for which the U.S. Bureau of Mines calculates a total world output. However, the economic well-being of any industry or group of industries cannot be measured solely in terms of the volume and/or value of its production, and examination of statistics reflecting other aspects of mineral industry performance shows that 1985 was a less than ideal year in many respects. In the case of consumption of mineral commodities, although there were gains registered in diverse sectors such as iron and steel, aluminum, fertilizer materials, solid fuels, and gaseous fuels, there were also proportionally small but notable declines in use among the older major nonferrous metals (copper, lead, tin, and zinc) and in the all-important liquid fuels. In the case of international trade in mineral commodities, although comprehensive data for 1985 were not yet available, there were indications that the value may well have fallen below the estimated 1984 level of $632 billion, although the volume may have increased slightly. This, if true, would be chiefly the result of declining prices of mineral commodities, and indeed, price declines were noted for a number of significant materials in terms of current dollars, and even more would register declines if calculated on the basis of constant dollars, adjusting for inflation.

Jan 1, 1987

By R. E. Heithecker

In June 1933 the Bureau of Mines, in cooperation with the State of Oklahoma and the Oklahoma City Chamber of Commerce, published a report of the gas at reserves in the Oklahoma City oil field3/ based upon data as of October 1932, at which time there were 43 classified gas wells in the field, The estimates were obtained by the ?porosity-area" method. There are two general methods of estimating natural-gas reserves. The porosity-area method, as used by Hill and Rawlins, is used when a gas field is comparatively new but after enough drilling has been done to determine the average thickness, porosity, and areal extent of the producing horizon. The "pressure-volume? method of estimating gas reserves, the method used in this report, nay be used after a sufficient volume of gas has bean withdrawn from the reservoir to cause an appreciable decline in reservoir pressure.

Jan 1, 1937

By W. K. Overbey

The Bureau of Mines conducted surface joint and stress measurements, airborne remote sensing imagery studies, compass-oriented borehole televiewer surveys, numerical simulation of fractured wells, and well productivity studies in a four-quadrangle study area of Ohio, to determine the effects of earth fracture systems on the deliverability of gas storage fields. The results of these studies indicate that much useful information about a gas storage reservoir can be obtained and put to practical use by studying--(1) oriented cores for fractures and directional permeability, (2) orientation of induced hydraulic fractures for alignment of well patterns, and (3) aerial photos and multispectral scanner imagery for general surface geology comparison and to determine if some, development patterns can be generated by such results. The absence of known tectonic elements associated with flat-lying sediments, such as faults or fracture zones that can be seen on the surface, indicates that the use of remote sensors such as radar or aerial photography is not likely to be useful in picking well locations for drilling. Studies similar to those discussed here should be conducted in gently folded and strongly folded sedimentary formation areas to determine if the increased knowledge of earth fracture systems under these conditions might be beneficial in gasfield and gas storage reservoir development.

Jan 1, 1974

[This Report represents the culmination of work perfomed under Contract No. .,JG1551A8 for the U.S. Bureau of Mine.The &apos;.:o-< embeded a site evaluation, engineering E:-y- ,, esign, and preparation of specifications for construction of a Transport Research 7 :4 (HTRF)The HTRF is designed as a research facility J evaluate the hydraulic transport of large lump coal at a prototype ;e scale. The HTRF is to be constructed and operated by the Pittsburgh and Safety Research Center of ;. re U.-AN a*, their Bruceton, Pennsylvania test center. In terms of technical capability, the HTRF will have transport pipeline:: of -, twelve-, and eighteen-inch diameter _&apos; with supporting coal handling n , water forage a.^ &apos;d conveyance, mixing, pumping, and dewatering equipment, plus instrumentation and controls. Maximum design velocity 13 20 ft/sec.; solids concentration, by, volume, will; 1 be a maximum-- of sixty, percent. Each test loop is designed to accommodate solids of up to one-third the diameter e - of the pine. The Final Report Pr.-&apos;I-rents information of t HTHF,. including the site evaluation, design criteria, a description of the a description of the procedure to be used for operation of the facility, an estimate of the cost to construct the f^Cilit:r, 1 p el_~lli.&apos;iU construe`, icn Schedule, and a construction suicJ_iicaT.l_ccn&apos;. T e c011SLr?Jc&apos;.ion soecl_ i.on _ccnta_i:s technic.&apos;..i re7,uir: (-n`,s for !&apos;urr1S~ &apos;~latcr..al. and ec-uipr,ent for :":C1 C_`:_C ti on of ti,_ H ice&apos; u:&apos;.:i ._II u s(-.6 for ~.Iir: .3!7 soliciting bids. `.l_o included n cc&apos;;,art_- c?r~.air sV:et..: :s ^nd rr^.?]

Jan 1, 1976

By N. Malakondaiah

Several growth chamber and laboratory experiments were conducted to study the germination behavior of plant species on mine spoils and plant growth responses to nutrients on spoils and topsoils. Experiments were conducted to study the germination potential of some native and introduced species under various conditions. The seeds of green needlegrass, side oats grama, thickspike wheatgrass, crested wheatgrass, birdsfoot trefoil and emerald crownvetch were less tolerant, whereas those of alkali sacaton. durar hard fescue, slender wheatgrass, yellow sweetclover and alfalfa were most tolerant to the sodic mine spoil conditions. Addition of leonardite improved the germination potential of some of the poor genninators. Slender wheatgrass and yellow sweetclover were used as test plants to study the fertility status and productivity potential of stockpiled topsoils and spoils collected from Center. Glenharold and South Beulah of North Dakota. The topsoils were neither saline nor sodic but low in N and P. The spoils were neutral to alkaline with SAIL of 12-32, EC of 1.8-5.5 mmhos/cm, Olsen&apos;s P< µ4g/g, and total N <0.07%. Application of N and P together to the topsoils increased the yield of wheatgrass and sweetclover by 88% and 70% of their respective maximum yields, whereas near maximum yields were obtained for both the species by the same treatments to the spoils. The average yields on topsoils were higher than the yields on spoils. The concentrations of major nutrients were higher in plants grown on topsoil, whereas the opposite was true with the concentrations of Mn, Zn, and Cu. Growth chamber experiments were also conducted to study the growth responses of alfalfa, oats and slender wheat grass by the application of Mn and Zn to a sodic coal mine spoil which was previously used for pot culture experiments. Significant growth responses to Mn and Zn were observed in alfalfa but not in oats or slender wheatgrass. Fertilizing the spoil with Mn along with NPK increased the yield of alfalfa to 85% and with Mn + Zn to 99%. Growth responses and plant composition results of this study confirm that the application of major nutrients to spoils can accentuate Zn and Mn deficiencies in some plants.

Jan 1, 1982

By Charles C. Boley

High-volatile A bituminous coal from the Allen mine, Las Animas County, Colo., blended with char produced from the same coal yielded accept-able metallurgical coke in a 500-lb movable-wall test oven. Nineteen experimental runs were carried out using several concentration levels of two different chars, 5.6 and 19.6 percent volatile matter, produced by entrainment carbonization of the base coal. With the higher-volatile char, an acceptable coke was produced at a 22.5-percent concentration; the lower-volatile char did not produce an acceptable coke at the concentrations investigated.

Jan 1, 1972

By Jesse A. Miller

ALTHOUGH the element titanium was discovered by William Gregor in 1790, over a hundred years passed before it was put to commercial use. The first commercial application of titanium was as an alloy additive to iron and steel, and the first ferroalloys were produced domestically in 1906. Titanium pigments were developed somewhat later and have been produced in the United States since 1918. The use of titaniferous material in welding-rod coatings first gained acceptance ill the mid-30&apos;s. The metal titanium has only had commercial importance since 1948; domestic production for that year was 10 tons. The relative importance of these major uses of titanium in various forms may he gaged by the consumption of titanium dioxide (Ti02) for these purposes in 1954. Of a total of 440,000 short tons of Ti02 consumed in 1954, 95 percent of the total was consumed for pigments; 2 percent for welding-rod coatings; 1 percent for non-titanium-base alloys and carbide; and 2 percent for miscellaneous uses. The titanium-metal industry is in its infancy, but it has more than doubled its output every year from 1948 to 1954, reaching 5,370 short tons in 1954.

Jan 1, 1957