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By J. A. Bartol

A survey was made of accident data and operating practices related to overloading and uneven load distribution on haulage trucks in noncoal open pit mines. Safety and economic aspects were analyzed. A bibliography of the literature was prepared. Review was made of available or projected systems for weighing or load indicating that might be applied to haulage trucks. A model specification was prepared for an overload detection system. Several promising systems for overload detection were identified. One was installed and tested briefly in a 170-ton rear dump truck in a copper surface mine.

Jan 1, 1982

By G. F. Kuncir

The analysis summarized herein evaluates the Bureau of Mines Program for Advancing Mining Technology Oil Shale in terms of the economic benefits which may be derived for the Nation as a result of its successful research and development efforts. On the basis of postulated oil shale production scenarios, benefit-cost ratio indicators are computed for the program elements as they apply to surface, underground, and modified in situ oil shale mining systems. Eight value indicators are used to measure the Program's beneficial impact on the future oil shale industry in relation to planned research and development costs. These are: capital cost savings, operating cost savings, labor savings, environmental quality maintenance cost reduction, reduction in production costs, byproduct production benefits, total production benefits, and additions to recoverable reserves. Program costs are aggregated from 1974 through 1987 and major benefits are accrued from 1982 through 2040. Both cost and benefit streams are discounted to mid-1975 present value.

Jan 1, 1977

By J. Sottile, J. L. Kohler

Component failures in the electrical control circuits of mining machines account for a large percentage of the total downtime of the machine. Once a failure has occurred it is always a tedious and usually a time-consuming task to locate the failed component. Moreover, the pressure to quickly locate the cause of a delay can lead to compromises in safety. Thus an onboard diagnostic system, essential for an automated machine, would be a very useful addition to existing machines. This report details U.S. Bureau of Mines development of a generic procedure for synthesizing diagnostic systems for electrical-control-circuit failures in mining machinery. A continuous mining machine is used as the testbed to illustrate the application of the developed methodology. Substantive differences among mining machine control circuits made it impossible to achieve a generic diagnostic system, but a generic approach for the synthesis of the diagnostic system was possible. As the research progressed, it became apparent that an algorithmic approach was better than an expert- system-based implementation. A prototype system was constructed and used to evaluate the diagnostic system. Prototype implementation issues are also examined.

Jan 1, 1993

By Ronald T. Mayerle

In-1992, the U.S. Bureau of Mines conducted a mineral investigation of the Anderson Mountain study area, including RARE II area 4-942, in Lemhi County, Idaho. The 7,340-ha study area lies within the Salmon National Forest about one kilometer north of the old mining town of Gibbonsville (pop.: 100). The eastern boundary of the study area is formed by the crest of the Bitterroot Range. The crest also serves as the continental Divide, and as the border between Idaho and Montana. The study area lies within the Gibbonsville Mining District, an important past producer of gold from lode and placer deposits. Since the 1870's, several hundred claims for both types have been located in the study area. Thirty-six current (1992) lode claims and two patented claim groups (one lode and one placer) are wholly or partially in the study area. No placer claims are current. In all, twenty-seven lode and five placer properties in and adjacent to the study area were investigated. Workings on the properties included 2 caved shafts; 36 caved adits; 8 open adits; 120 small pits, cuts, and trenches; and 4 large dozed cuts.

Jan 1, 1993

By Roger E. Burleigh

In June, 1989, the U.S. Bureau of Mines, undertook a 9-day evaluation of the tin resource potential of the Sleitat Mountain tin deposit. Significant tin-tungsten mineralization is associated with quartz-topaz-white mica-tourmaline greisen alteration of a multi-unit, 57 Ma, peraluminous, granite stock which intrudes Cretaceous Kuskokwim Group flysch deposits. The granite comprises marginal biotite-, intermediate biotite-muscovite-, and central zinnwaldite-granite units, interpreted as a zoned alteration system. Major vein mineralization is confined to two east-west-trending zones of steeply oriented tabular lenses of greisen interleaved with mildly altered granite. Cassiterite is the dominant ore mineral while arsenopyrite, loellingite, wolframite, pyrite, sphalerite, chalcopyrite, and bismuth-oxides are present in minor to trace amounts. The north and south greisen zones are estimated to contain an inferred resource of 128 to 212 million lbs Sn in 28.6 million st of mineralized rock. An 1,800-lb representative bulk sample contained 0.37% Sn, 0.04% W and 17 ppm Ag and is considered an average grade estimate for the deposit. Drill testing by Cominco Alaska Exploration indicates that substantial widths of high-grade tin mineralization are included within the lower grade disseminated mineralization. Depth of deposit erosion is substantial and there exists a high probability for placer tin deposits.

Jan 1, 1991

By Lisa A. McDonald

The environmental compliance process affects all aspects of hardrock-mining operations, from exploration through post-closure. The primary components of the environmental compliance process are requirements under the National Environmental Protection Act of 1969 (NEPA) and the permitting requirements associated with various other federal, state and local laws. This study considers the Greens Creek Mine and the development of two other projects (Alaska-Juneau & Kensington). These mines were used as the foundation for a case study of the impacts of the environmental compliance process on hardrock-mining activity in Southeast Alaska. The case study presents the institutional and legal requirements, followed by a discussion of the impact of this process on the production and timing of the three mines. The results of this preliminary study reveal some interesting findings, some expected and others unexpected, regarding the impact of the permitting process on the exploration, development and (proposed) operation of the three mining projects in the Juneau area. Determining the cost of compliance with these requirements is an important step in evaluating the appropriate course of action to protecting the environment while providing the necessary raw materials needed for society. This preliminary study highlights the initial starting point for such an analysis.

Jan 1, 1992

By Donna L. Anderson

The first section of this U.S. Bureau of Mines report includes a discussion of the navigational tasks performed by operators of mobile mining equipment, with the focus on the navigational information and guidance techniques required by continuous mining machine operators. Some previous research and attempts in remote and autonomous navigation of continuous mining machines are mentioned. Issues of research in autonomous navigation of various other mobile robots are presented, with attention focused on their applicability to a continuous mining machine navigating in the mining environment. Conclusions are stated on methods of automating the navigational tasks of a continuous mining machine, and a decision to concentrate initial attempts on the tasks of autonomous face navigation is defended. The second section of this report includes a presentation of the Bureau's proposed solution for autonomous face navigation of a continuous mining machine, which includes the employment of a mobile roof support as a reference for guidance in the face area, and a navigational guidance system for the continuous mining machine.

Jan 1, 1989

By F. W. Wood

ORIGINAL experimentation in specially designed arc-melting furnaces and a comprehensive review of technical literature have helped with an understanding of electric arcs as used in metallurgical applications. Results relevant to the distribution of electric potentials and currents, temperatures, pressures, the consumption of electrodes, the identities of particles participating in electrical conduction, and the modes and mechanisms of discharge are presented and discussed. Present knowledge of high-current arcs is insufficient to test pertinent theoretical suggestions. However, the chief doubts concern the identities and the liberation or formation of current-carrying particles. It seems that either (1) novel formulations of existing concepts are needed, or (2) essentially new concepts must be recognized to explain observations. An analysis of the situation has led the authors to favor the latter possibility and to suggest the existence of supplementary conducting particles. The conduction of current by the streaming of charged agglomerates is postulated. Another outgrowth of analysis is an equation for the arc potential as a function of current densities in the arc. In lieu of conclusions, the potentialities of practical applications and specific needs for fundamental clarification are summarized.

Jan 1, 1965

By R. L. Marek

The number of persons fatally injured in the California petroleum industry in 1931 was 30, a decrease of 20 fatalities or 40 per cent from the number killed in 1930. As a result of the decrease in the number of fatalities for 1931, the fatality curve of tie California petroleum industry reached its lowest point in nine years. Although reductions in personnel--which permitted the retention of a select and experienced class of workmen, decreased active field-development work, and curtailed production--undoubtedly have had a marked effect on reducing the number of fatalities in 1931, the decrease also has resulted from continued accident-prevention efforts. Statistics show that a direct relationship exists between development activity and the number of men accidentally killed in the drilling and producing division of the California petroleum industry. For example, when the average number of drilling wells in 1930 was 29 per cent less than in 1929, the number of men accidentally killed at drilling wells dropped 48 per cent; and when the average number of drilling wells in 1931 decreased 52 per cent from 1930, the number of fatalities at drilling wells decreased 58 per cent. The relationship between field-development work and fatality frequency is significant because each year at least 50 per cent of all the fatalities in the California petroleum industry occur in the drilling and producing division. This relationship should serve to guide the accident-prevention efforts of the industry, especially in the drilling and producing division, toward checking an increase in fatal accidents when development activity again takes an upward trend.

Jan 1, 1932

By V. B. Dale

This report is one of a series covering the mineral resources of the Nation. It briefly describes most of the known tungsten deposits in Gila, Yavapai, and Mohave Counties, Ariz. Many of the descriptions are taken from the reports of previous examinations by Bureau of Mines engineers, and from Defense Minerals Exploration Administration files. Where a previous examination had been made, and an inquiry disclosed that little or no work had been done since that time, pertinent information from the report was used in this paper with acknowledgment of the source. However, the majority of the descriptions is from field examinations by the author. In the past 3 years (July 1956-May 1959) only necessary annual assessment work was conducted on nearly all the properties described in this paper. There was no active mining on any of the properties examined.

Jan 1, 1961

By Roy E. Peterson

The Bureau of Mines conducted bench-scale research to evaluate materials which showed potential as low-cost reductants for use in the ironmaking industry. These materials were lignite, subbituminous coal, coal char, tree trimmings, refuse--derived paperboard, used crankcase oil, and peat. To compare their effectiveness, the materials were tested in the reduction roasting of nonmagnetic taconite and, except for oil and peat, in the reduction of iron oxide pellets to metallized pellets. Reduction was conducted in a 18-cm-diameter, rotary drum, which was externally heated in an electric furnace. Over 92 pct of the iron was magnetically recovered from a nonmagnetic taconite after roasting with any of the reductants, but greater quantities of reductant were required to achieve this when the waste materials were used. The fossil fuels were also more effective for metallizing pellets, although metallizations above 90 pct were also obtained with tree trimmings and refuse paperboard. However, refuse paperboard had to be frequently recharged to the furnace because it depleted rapidly.

Jan 1, 1983

The first metal-mine accident-prevention course was prepared and published in 1942-45 as a series of seven miners' circulars (Nos. 51-57). The scope of the course has been broadened, revised, and brought up to date, and it is being published as a similar series of seven miners' circulars on accident prevention in metal and nonmetallic mines. These circulars are: 1. Accident Statistics (Miners' Circular 51), dealing with general statistics on accidents and injuries at metal and nonmetallic mines, including causes, costs, and the uses of investigations and reports of all accidents.

Jan 1, 1957

By John W. Mentz

Phase I study efforts addressed: 1) acid mine drainage formation theory; 2) effects of inundation in reducing acid mine drainage formation; 3) summary information on the types of acid abatement technology currently available and the problems inherent in each; 4) analysis of two potential means of partially inundating abandoned segments of active underground mines to reduce acid formation. This subsequent Phase II Draft Final Report addresses all of the above, but concentrates on and defines Item 4. Seal construction techniques were taken through five logical steps as follows: A) Location Analysis; B) Coal Barrier Pillar Analysis: C) Ground Water Analysis; D) Design Considerations: E) Economic Analysis. The design details of both low wall dams and section seals were discussed in a series of segments: a) Case Histories; b) Feasibility Analysis; and c) Design (including representative calculations). Study efforts showed that both concepts are feasible only in certain mines where the geologic-hydrologic physical makeup is suitable to contain a mine pool. Low wall dams in particular were found to have extremely limited applicability as a means of pollution reduction. Section seals, while clearly dependent upon site specific conditions, have a some what broader range of utility and are more effective in pollution reduction. The proven dramatic reduction in acid mine drainage attributable to inundation makes this a concept that must be considered.

Jan 1, 1981

By K. R. Dorman

To develop the potential of precast concrete sets as a support medium in underground mines, a three-piece precast concrete drift set was designed for a small opening and tested to destruction in an underground straining frame. Thirty-six tests were made with three sizes of members using three different loading conditions. In addition, 14 members were tested individually in the laboratory. Test results are compared with theoretical calculations. A cost comparison shows the use of concrete sets would be advantageous where conventional wooden timber requires excessive replacement.

Jan 1, 1968

By D. B. Lovett

The work described in this report was directed toward identifying and devising methods to minimize the previously observed variability between working level hour exposures and the alpha particle track densities resulting on Track Etch films exposed to mine atmospheres containing radon and radon daughters. The disequilibrium between radon and its daughters was shown to directly affect this Track Etch film calibration factor. The wide range of disequilibrium states possible in mine situations amply explains the variability in the previous tests. A file of published mine atmosphere composition data was compiled and was used, along with atmospheric compositions derived from several theoretical models ref the atmospheric behavior, to evaluate the variability of several dosimeter configurations and concepts. A nonlinear, iterative regression analyse; was formulated that successfully predicted working levels to within 8 to 10% from only the alpha particle activities (Rn, RA, and RaC') data such as are obtainable from Track Etch films over a wide range of disequrlibrium conditions. A model expressing atmospheric concentrations as a function of radon source strength, plate out rate factor, ventilation rate and the fractional re-entry by recoil of previously platted-out daughters was derived and used in the regression program in addition to preparing a set of reference tables and graphs showing the disequilibrium behavior of the atmosphere. Other factors that can affect the Track Etch Film response writ considered and shown to he less crutial than the disequilibrium state. The results of a series of exposures of a dosimeter concept fixture in the Denver Mining Research Center radon chamber air presented and discussed.

Jan 1, 1976

By Forrest T. Moyer

Frequency rates of injuries per million man-hours of exposure were improved during 1965 slightly to moderately over those of 1964 at metal mines, nonferrous reduction and refining plants, nonmetal mills, stone quarries and mills, sand and gravel operations, and slag operations. However, at metal mills and nonmetal mines the rates of occurrence of work injuries were less favorable. The severity rates of injuries during 1965 were better than in 1964 at metal mines and mills, stone quarries and mills, and slag operations. Conversely, severity rates were worse at nonferrous reduction and refining plants, nonmetal mines and mills, and sand and gravel operations.

Jan 1, 1966

By J. I. Paige

The Bureau of Mines studied methods for recovering unreacted titanium minerals and petroleum coke from titanium chlorination plant wastes prior to neutralization treatment with lime. The objective was to recover valuable raw materials and to reduce the amount of waste materials that must be treated for disposal. Samples of solid wastes were physically beneficiated by gravity concentration (tabling) to recover titanium minerals containing 69.0 to 92.4 wt-pct Ti02 and by selective carbon flotation to recover petroleum coke containing 94.0 to 96.8 wt-pct C. Laboratory data indicate that the recovered titanium mineral would decrease the amount of solid waste to be disposed of from 32.8 to 53.9 wt-pct. The recovery of coke would further decrease the amount by additional 32.9 wt-pct. Preliminary tests conducted on recovering vanadium, chromium, and columbium from liquors obtained by leaching chlorination residues also have shown that (1) 97 pct of the vanadium was extracted from leach liquors in a two-stage solvent ex-traction procedure and (2) 58 pct of the columbium and 40 pct of the chromium were separated from the leach liquors by an ion exchange technique using a strong acid resin.

Jan 1, 1982

By R. A. Cattell

The Bureau of Mines actively conducted a well-coordinated research pro- gram during the past fiscal year on problems dealing with the production of oil and gas, transportation of natural gas, chemistry and refining of petrole- um, thermodynamic properties of hydrocarbons, and the processing and utiliza- tion of incombustible helium gas. These particular reserach phases, compris- ing the presently scheduled activities, are integral parts of a broad program selected soon after the war as suitable for Bureau of Mines study, to meet immediate needs for specific information on petroleum and natural-gas problems of national scope. Important progress was made and many technical reports were finished during the year. Several reports were published on gas-condensate production problems, one giving the results of laboratory tests of relative merits of various steels and alloys for rosisting the corrosion that occurs in high-pressure gas- condensate wells. Research was continued, using the Bureau's windowed cell, to determine the characteristics of gas-condensate fluids, and an important paper on the phase relations of these fluids at low temperatures was published. An important part of the Bureau of Mines petroleum production research program for many yoars has been the engineering study of type oil fields. This year reports waro completed on the Lake Creek, Sheridan, and West Rod River fields, Tex.; the Atlanta field, Ark.; and the Bogge field, W.V. Othor fields under study and for which reports will be issued are the Carthage and Now Hope fields, Tex., and the Weber pool, Okla. Spocial studios to determine the characteristics of the oil-gas solutions as they exist within the native reservoir rocks have been in progress in the North Lindsay field, Okla.; the Elk Basin field, Wyo. and Mont.; and the Rangely field, Colo. The North Lindsay study brought to light several un- usual physical proporties of the oil as it is found in this deep-seated reservoir. For instance, its viscosity is less than that of water, and more than 2 barrels of the initial reservoir oil must be produced to yield 1 barrel of "stock-tank oil." In the Elk Basin and Rangoly fields the oil-gas solution varies in composition within the reservoir, depending upon structural location. Engineering studies were continued on woll spacing and on drilling fluids with special emphasis on obtaining uncontaminated cores, or coros for which the flushing action of the drilling fluid can be dotormined accurately. In connection with research on production of oil by secondary recovery methods, progress was made in studies of conditioning water for subsurface injoction, of input ratos and pressures for water-flooding oil sands, and of the selective plugging the more permeable mediurs to prevent or retard channel- ing of the injected fluid. The availability of fuels for all types of internal-combustion engines still is tho primary resoarch project in potroleum chomistry and refining. This rosearch program is subdivided into a sorios of problems under four main topics: (1) Raw-material studios; (2) relationships of fuel consumption, proporties, and performanco; (3) utilization of potroleum products; and (4) analytical mothods, which include chomical and physical property detorminations.

Dec 1, 1949

By D. A. Stanley

The Bureau of Mines conducted laboratory-scale experiments to determine whether or not surface waters with a high organic content could be purified sufficiently to be used to replace the natural high-quality deep well water currently being used in the silica flotation step of phosphate rock beneficiation. Waters abundant in organic matter were collected from two central Florida streams, flocculated with a cationic polyethylenimine polymer, and processed in a sand filter. This treatment removed most of the organic materials from the water. Untreated surface water, treated surface water, and distilled water were used to compare the flotation response of the acid insolubles in an amine flotation circuit. Surface water treated with PEI-1000 was shown to be as effective as distilled water for the acid-insoluble-flotation step. Flocculation and filtration can therefore produce water suitable for amine flotation of quartz, which would permit substitution of surface water for deep well water.

Jan 1, 1981

By K. C. Dean

The Bureau of Mines, following passage of the Solid Waste Disposal Act of 1965, was authorized to conduct research on methods for utilizing, stabilizing, or reclaiming mineral wastes. This report summarizes laboratory research conducted by the Bureau and cooperative field studies made with the mineral industry to reduce the environmental impacts of air and water pollution deriving from mineral wastes. Utilization research showed that both dry-press and steam-cured building bricks and ceramic tile could be made from copper mill tailings and other discarded mineral wastes. Sponge iron was produced from steel mill and amination industry wastes, and valuable mineral products were extracted from such diverse sources as flue dusts and uranium tailings. Mineral wastes were combined with agricultural and/or sewage wastes to make artificial soils that have the potential of resolving several disposal problems by production of a useful commodity. Physical, chemical, and vegetative stabilization methods were evaluated, singly and in combination, for reclamation potential on copper, uranium, lead-zinc, and asbestos tailings. Suitable methods were developed in the laboratory for overcoming major adverse conditions of these wastes such as salinity, heavy metal toxicity, acidity, basicity, lack of nutrients and organics, and unstable surfaces. Field testing of these methods was performed on a variety of mineral wastes. Costs for the various stabilization and utilization-procedures developed were also determined.

Jan 1, 1986