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By Fred E. Fiedler

A demonstration project investigated the feasibility and effectiveness of two management interventions, Management Training and Organization Development, for improving productivity and safety in metal/non-metal mines. The management training intervention was conducted at Texasgulf Company's trona mine, using three nearby trona mines as controls. The Organization Development intervention took place in Hecla Mining Company's Lucky Friday mine, using the highly similar Star Mine as control. The two management interventions seemed about equally effective in reducing accidents and injuries, as well as MSHA citations, and the management intervention at the Texasgulf mine also appeared to have led to substantial improvement in mine productivity.

Jan 1, 1983

By Ronald Branstetter

Gaseous and particulate exhaust emissions from 20 diesel engines in service at five underground mines were measured with high accuracy instrumentation. The engines that were tested were checked for faults or maladjustments. The vehicle and engine maintenance organization was studied at each mine and an idealized maintenance program was devised. Faults were induced in a new diesel engine to determine their effect on the characteristics of the exhaust emissions. The results, conclusions and recommendations from this investigation are presented in this final report.

Jan 1, 1983

By E. A. Mevissen

With the ever increasing consumption of mineral commodities, the vital question is not whether sufficient mineral quantities will be available, but rather can the known existing low grade resources be mined economically. Conventional conveyor systems are being used in some open pit mines to decrease haulage costs. n an effort, to take this concept one stop further, this contract study examines the use of a high angle conveying system in an open pit mine. It identifies available high angle conveying equipment and examines the haulage and crushing costs associated with both a conventional truck and shovel mining operation and a high angle conveyor operation. These costs analyses were performed on a hypothetical copper, taconite and phosphate mine. Information was gathered from a series of high angle conveying equipment and open pit mining operations in the U.S. Volume I includes a detailed review of the state-of-the-art in high angle conveying concepts, the, hypothetical mine development, and the cost analyses. Volume II includes the appendices.

Jan 1, 1981

By Reynold Q. Shotts

A study was made of the coal resources of an area in Jackson County, Ala., forming a part of the Flat Rock, Henegar, and Stevenson quadrangles. The area studied is a portion of the Plateau coalfield on Sand Mountain and is near the Tennessee Valley Authority's Widows Creek steamplant. Since no detailed geological study of this area had been published, some reconnaissance work was done. The coalbeds and adjacent strata such as sandstones, conglomeratic sandstones, and conglomerates were studied. Available drill logs, together with the areal geology, provided sufficient information to permit correlation of the coalbeds and an estimation of coal reserves. For all categories of reserves, computed on a regional basis, a total of 72,920,000 tons of coal more than 14 inches thick is estimated for the areas studied in Stevenson. Flat Rock, and Henegar quadrangles. Of this tonnage, 40,001.000 tons is estimated to have less than 60 feet of overburden. The total measured coal reserves for the above three quadrangles are 16,359,000 tons, with 12,471,000 tons under less than 60 feet of cover.

Jan 1, 1966

By K. E. Robinson

This study is the extension of an investigation of reclamation of floodplain areas in the Coeur d'Alene Mining District, Idaho, that are unuseable in their natural condition, by construction of landfills with mill tailings. The study develops a valley-wide tailings disposal plan to utilize 20 potential landfill sites on floodplain areas and presents measures for reclaiming the sites for subsequent productive use. Field and laboratory testing on a test section and two abandoned impoundments support the use of hydraulically deposited tailings for landfill construction. Hydrological testing has shown that controlled discharge from tailings impoundments results in contaminant levels in the discharge below regulated standards. Additional testing indicated that compacted soil liners and pond management provide adequate contaminant abatement where acid-generating tailings are encountered. Mechanical compaction, including surcharge loading, upgrades foundation support capacity so that construction on the surface of tailings deposits is feasible. On completion of the testing program, the test sections were abandoned and rehabilitated. Details concerning potential landfill sites have been refined. At recent production rates, the 20 sites would result in 680 acres of reclaimed land, while providing a minimum of 40 years of tailings storage capacity. A general design has been developed for the retention dikes. Aspects of embankment stability, including liquefaction are discussed, and are shown to provide an adequate factor of safety under the anticipated range of operating conditions.

Jan 1, 1983

To allow routine measuring of the exposure of underground workers to N02 from diesel engines and residual gases from blasting. The Approach: A miniature sampler absorbs NO2 which can be measured using a simple method adaptable to both multiple automatic analyses or individual on-site analysis. How It Works: The NO2 sampler is encased in a plastic tube approximately half the length of an ordinary ball point pen and clipped to an underground worker's hard hat. Removal of the end cap activates the personal sampler. Air from the working place enters the open end and diffuses at a controlled rate down the tube interior. The diffusion rate is dependent on tube dimensions (ratio of cross-sectional area to length). The closed end of the tube contains stainless steel mesh which is coated with triethanolamine (TEA) for absorbtion of all NO2 reaching it. Other oxides of nitrogen are not absorbed. The amount

Jan 1, 1975

By Robert W. Waytulonis

Mining regulations pertaining to the use of diesel engines were solicited from foreign countries with mining operations by the Bureau of Mines. Responses were received from 27 countries; the information received and U.S. regulations were reviewed, and those parts pertaining to the use of diesel engines in underground mining were synopsized according to the following subject categories: types of engines permitted, testing and certification procedures, fuel quality specifications, emission control requirements, procedures and frequency of testing exhaust gases, mine air quality and quantity (ventilation) requirements, procedures for testing mine air quality and quantity, and noise standards. All categories except the types of engines permitted and testing and certification procedures are summarized in tables. Contacts are provided for each country to facilitate inquiries concerning regulation revisions or interpretation.

Jan 1, 1987

By J. W. Adams

Two different techniques were wed to make measurements of the absolute value of electromagnetic noise in an operating hardrock mine, Grace Mine, located near Morgantown, Pennsylvania. Diesel-powered haulage equipment is used in this mine, and the electromagnetic noise environment it creates was measured to see how it differs from the environment created by electric-powered haulage equipment. One technique measures noise over the entire electromagnetic spectrum of interest for brief time periods. Data are recorded using broadband analog magnetic tape and are later transformed to give spectral plots. The other technique records noise amplitudes at several discrete frequencies for a sufficient amount of time to provide amplitude probability distributions. The specific measured results are given in a number of spectral plots and in amplitude probability distribution plots.

Jan 1, 1974

By J. W. Allen

This report reviews the work performed on Task M of Bu-Mines Contract H0220073 to develop an engineering model of a surface and subsurface communications system for normal mine operations and for post disaster rescue operations. The system concept provides for one-way transmission of digital information between a number of identifiable subsurface terminals or subcenters and a single surface station. It also provides 2-way voice communications between the subcenters and the surface station. The basic communications link is electromagnetic signaling through-the-earth, but the system is also capable of using mine phone lines as an alternate link. Engineering models of three subcenters and one surface terminal (see Figure 1-1) have been fabricated in order to demonstrate the system's performance. The system concept, however, permits up to 20 subcenters to be incorporated if desired. Additional subcenters are also feasible for large mines if they can be deployed in the mine to operate on a noninterfering basis.

Jan 1, 1973

By D. V. Gaffney

This report presents the results of a three-phase investigation of the feasibility of using cemented coal waste in active underground coal mines to prevent mine subsidence. Coal caste was broadly defines to include waste from both coal preparation plants and coal-fired power plants. Underground systems with potential for cemented backfill are determined through identification of current mining methods and available technologies for cemented backfilling and consideration of materials and systems constraints upon mining and backfilling integration technical concerns including operation, health and safety, materials utilization, environmental impact, applicability and techni¬cal status are assessed for six (6) systems which were identified as potentially feasible. Two (2) of these systems are conceptualized in a hypothetical case history and developed to further assess their operational and economic feasibility. Comparisons of costs among both systems and with costs of surface disposal are presented. Also presented are the conclusions reached concerning the present feasibility of using cemented backfill in active coal mines and potential avenues for further research. Appendices contain further consideration for design of cemented mixtures to be used in backfilling, the results of laboratory testing of mixtures rich varying concentrations c: waste products and cementing agents, and an annealed bibliography

Jan 1, 1981

By W. W. Weller

Heat capacity measurements of anhydrous cobalt sulfate (CoSO4), copper sulfate (CuSO4), nickel sulfate (NiSO4), and zinc sulfate (ZnSO4) were conducted over the temperature range 51° to 298° K. The results were used to evaluate the following entropies at 298.15° K (cal/deg mole): CoSO4, 28.1; CuSO4, 26.8; NiSO4, 24.8; and ZnSO4, 26.4. Entropies were combined with heats of formation to give free energies of formation.

Jan 1, 1965

By A. George Stern

[In the examination of bentonitic clay suspensions used for oil-well drilling fluids3/ (and for other purposes, such as a core binder for foundry sand) it is important to have comparative tests for evaluating them. A satisfactory clay for these and other purposes should have the property of forming what is commonly called a "gel," but the measurement of this property has been a real problem. To date the solution has not been satisfactory, and some of the difficulties are considered in, this, paper, which describes a simple form of instrument (identified as an eykometer) for measuring the yield point under hydrostatic conditions of non-Newtonian clay suspensions, including those muds that are thixotropic. An oil-well drilling mud serves several functions, many of which depend on the "gel" characteristics of the mud. Among the more important functions are: (a) To plaster the sides of the hole to prevent caving of the walls; (b) to prevent the loss of the circulating fluid out of the hole by seepage; (c) to carry sand and cuttings out of the hole to the surface as they are formed by the rotary drill; and (d) when circulation of the fluid stops for shut-down or other unavoidable cause, to hold the cuttings in suspension by the setting up of the gel, thereby avoiding the difficulties that result when these cuttings are allowed to fall through the fluid and pack at the bottom of the hole.]

Jan 1, 1940

By R. V. Ramani

One area of study in the Coal Mine Injury Analysis project was to illustrate and enhance the ability of mine safety management personnel to apply analytical techniques to injury experience data and to justify requests for funds for safety enhancement actions on a cost/benefit and other quantitative basis. Four volumes of this final project report detail (1) the objectives and scope of the mine safety management research, (2) the results of literature review, and case studies, and (3) models developed for mine safety management. The four volumes are titled as Volume III: Mine Safety Management, Volume IV: Analytical Techniques for Mine Safety Management; Volume V: Mine Safety Management Case Studies and Volume IX: Training Cost Model. In this volume, the quantitative procedures that have been developed for the mine-specific analyses of accident/injury experience data are presented and their applications are demonstrated in a summary form through case study examples. The quantitative procedures will aid mine safety management personnel to develop focused accident prevention strategies including training, as well as to justify the investment in such proactive programs through cost-benefit analyses.

Jan 1, 1993

By A. George Stern

In the examination of bentonitic clay suspensions used for oil-well drilling fluids3/ (and for other purposes, such as a core binder for foundry sand) it is important to have comparative tests for evaluating them. A satisfactory clay for these and other purposes should 'rave the property of forming what is commonly called a "gel," but the measurement of this property has been a real problem. To date the solution has not been satisfactory, and some of the difficulties are considered in, this, paper, which describes a simple form of instrument (identified as an eykometer) for measuring the yield point under hydrostatic conditions of non-Newtonian clay suspensions, including those muds that are thixotropic. An oil-well drilling mud serves several functions, many of which depend on the "gel" characteristics of the mud. Among the more important functions are: (a) To plaster the sides of the hole to prevent caving of the walls; (b) to prevent the loss of the circulating fluid out of the hole by seepage; (c) to carry sand and cuttings out of the hole to the surface as they are formed by the rotary drill; and (d) when circulation of the fluid stops for shut-down or other unavoidable cause, to hold the cuttings in suspension by the setting up of the gel, thereby avoiding the difficulties that result when these cuttings are allowed to fall through the fluid and pack at the bottom of the hole.

Jan 1, 1940

By W. W. Aljoe

The use of protective canopies can result in canopy roofing and/or serious restrictions to operator comfort and vision. To document this experience, BCR conducted a field study of cab and canopy design and application which resulted in a catalog of 164 canopy designs and an analysis of field data which showed no simple relationship between working height and canopy-related problems. The relationship also involves (1) machine frame height, (2) mine floor undulations, (3) operator compartment dimensions, (4) canopy design and location on the machine. Data analysis indicates (1) present technology does not always permit successful application of canopies in working heights below 42 inches, and (2) development of satisfactory low-coal canopies is doubtful. The basic conclusion of the study is that future R&D studies should be directed at development of alternative protection systems and remote mining methods.

Jan 1, 1981

By Donald E. Ralston

The Huntsville study area in northeastern Alabama consists of Jackson, Limestone, Madison, and Marshall Counties. Major emphasis was placed on the Huntsville urban area in Madison County to analyze the relationship of urban growth and the minerals industry. Huntsville was delineated into its component urban, suburban, and rural parts for 1964, and the primary area of growth was predicted for 1990. Population estimates were made for the four-county area as a unit and Madison County separately, and projected to 1990. Demand estimates for crushed stone and sand and gravel were made for the same area units and projected to 1990. Analysis of quarry sites in the Huntsville area was made for the present and for the future. The mineral operations of the study area are all located in rural areas; in the case of Huntsville, the mineral sites are located in areas defined as "rural" in the component urban-suburban-rural system. The operations outside Madison County can expect to have minor problems with urban encroachment, while those operations in Madison County can expect major problems associated with urban growth and development. Some of the problems associated with limes tone production can be reduced if producers invest in capital equipment that will reduce the nuisances inherent in this activity. Although urban expansion endangers some quarry operations in Huntsville, topographic and political restrictions which prevent urban expansion can effectively shield quarry operations for some time.

Jan 1, 1970

Mine drainage and mine reclamation are topics of major interest to the mining industry, federal and local governments, and the general public. This publication and its companion three volumes are the proceedings of a conference held in Pittsburgh, Pennsylvania, April 24-29, 1994. There were twelve sessions (69 papers) that dealt with mine drainage, including modeling, geochemistry, prediction, treatment, control strategies, characterization, hydrology, and case studies. These sessions comprise volumes 1 and 2. The six sessions (34 papers) that dealt with reclamation and revegetation of disturbed lands are included in volume 3. Volume 4 includes the six sessions (34 papers) that dealt with such topical issues as fires at abandoned mine sites, subsidence, hydrology, mine wastes, and policy. Poster session presentations are represented by 49 papers and 92 abstracts that have been placed in the back of volumes 2, 3, and 4, consistent with the subject of that volume.

Jan 1, 1994

By Mark I. Copeland

This study was conducted by the Bureau of Mines to determine the effect of steel reheating practices in burning natural gas on the amount of silicon required to prevent the formation of copper on steels containing up to 1 wt-pct Cu. Formation of copper, which causes surface hot shortness, was readily prevented by as little as 0.3 wt-pct Si and by 2 vol-pct excess oxygen in the furnace atmosphere when reheating steels containing up to 0.8 wt-pct Cu. Up to 0.8 wt-pct Si content and careful control of reheating conditions were necessary for steels containing 1 wt-pct Cu. Best conditions for these steels were reheating to 2,200° F (1,205° C) in burning gases containing 2 vol-pct excess oxygen, and then to higher temperatures in gases of 6 vol-pct excess oxygen. Slag and mold wash were not detrimental on steels reheated for 8 hr by a soaking-pit-type furnace schedule, but they were problematical on steels heated for 2 hr by a pusher-type furnace schedule. The effect of silicon contents on scaling rates also was determined.

Jan 1, 1974

By Rodney D. Rosenkranz

The Bureau of Mines evaluated the potential supply of primary copper from domestic mines and deposits and found that increases in copper price will be required in order for many domestic deposits to continue production. As part of the study, a tonnage-price relationship was developed indicating the quantity of copper that could be produced economically from known deposits at various copper prices and at various rates of return on the required capital investment. Costs of production are based on estimated capital and operating costs for mining, concentrating, transporting, smelting, and refining. Direct and indirect operating costs, recovery of investment, and return on investment have been included in the smelting and refining costs. Capital and operating costs are calculated in January 1978 dollars, and byproduct credits are based on January 1978 prices. Known domestic copper mines and deposits contain nearly 92 million metric tons of copper in about 14 billion metric tons of demonstrated mineralized material. These tonnages represent the current domestic copper reserve base. Approximately 74 million metric tons of copper are recoverable from the reserve base using existing technology. Of this quantity, slightly more than 50 million metric tons are economically recoverable assuming a price of 51.00 per pound of copper, credit for the recovery of byproducts, and a 15-percent rate of return on capital investment. Approximately 60 percent of the copper occurs in mines that were producing at the time of the study.

Jan 1, 1979

[This Bureau of Mines report presents results of a survey of underground mining equipment and of two demonstration programs showing the feasibility If quieting; a load-haul-dump (LHD) machine and a personnel vehicle. Typical noise levels are presented for the major machine types used in underground mines, along with estimates of the noise overexposure of miners who operate or work near these machines. General principles of noise control are explained, and the application of these principles is illustrated in the description of modifications made to the LHD machine and the personnel vehicle. The noise control package installed On the persona of vehicle lowered its noise level by 14 dBA after 4 months of operation, and inspection of the LHD machine after 2 1/2 years of operation with the modifications showed its noise level 7 dBA lower than that of the unmodified machine. Noise dosimeter measurements indicated that both machines were in compliance with Federal noise regulations for a typical shift.]

Jan 1, 1980