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By Donald S. Colby

This Bureau of Mines report is essentially a handbook, or manual, for making the type of mineral resource valuation commonly required for such public policy problems as mineral leasing. The principle of resource valuation through the capitalization of cash flow is well established. A mathematical procedure, based on a simplified accounting system, is detailed for calculating cash flow from revenue, plant costs, and operating expense. Variations of procedure cover cost depletion, percentage depletion, and depletion limited to 50 percent of net income. The influence of the depletion provisions of the tax regulations on the value of a resource to an owner and to an operator is analyzed. The relationship of royalty, bonus payments, and sales price to resource value is also described, and methods for approximating resource values using these payments as input data are developed.

Jan 1, 1969

[1.1. The provisions of this code are minimum provisions and are designed to minimize hazards to life and property in and about underground coal mines where electrical equipment and circuits installed used. They indicate the Steps necessary in the selection, installation, operation, inspection, and maintenance of electrical equipment and circuits to obtain proper safeguards in reducing electric shock, fire, explosion and other hazards. Surface as well as underground installations were considered in formulating the code and, unless otherwise stated, each provision applies equal to both underground and surface installations. This code does not apply to buildings and installations not directly connected with mining operations, nor does apply to strip-mining operations.]

Jan 1, 1952

By B. J. Moore

This publication contains analyses arid related source data for 274 natural gas samples from 20 States. Of the total samples, 269 were collected during calendar year 1985; the reminder were collected earlier, but releases granting permission to publish were not received before 1986, All samples were obtained and analyzed as part of Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free market economies. This survey has been conducted since 1917. The analyses published herein were made by mass spectrometer and chromatograph.

Jan 1, 1987

By Lloyd Williams

1. The investigation shows that the Coal Creek has been the most productive, bed in Campbell County and contains the largest recoverable reserves of coal. The Pewee, Red Ash, and Jullico have been relatively productive beds and contain appreciable recoverable reserves of coal. The Blue Gem also has been productive in the past, but available information indicates that most of the remaining coal is Less than 28 inches thick. The Big Mary has relatively large reserves over 28 inches thick, but the coal is high in ash and sulfur. Thick partings in the Windrock bed have discouraged mining in that bed. The Poplar Creek and Rex beds generally are below drainage, and large areas have been excluded from the reserve estimate, Reserves in the Walnut Mountain bed will be difficult to mine due to the irregu¬lar thickness and lack of continuity of the bed. Estimated coal reserves are- small in the remaining five beds. 2. 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 398 million tons as of January 1, 1953, o? this total, 267 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 to make 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, these should be added to the total estimated reserves.

Jan 1, 1956

By Albert L. Toenges

[sing tho ppsf; few Yomn t!le:.c. hcs beer. p. trqnd away frorn locomotive haulwe of cop2 frorn tile losdiw point to tho prop,nration plant of bitu~i- nnus-cod strip mlncc to a;~to~lzcd. h,71Jlr.:~. The qrostion has arisen rrhethcr this is alwqvs econ~nicd, rxcl the purpcrse or' tnf s investigation is to de- termine, if possible, the econonic limlt for ~~torieod had.we. sing tho ppsf; few Yomn t!le:.c. hcs beer. p. trqnd away frorn locomotive haulwe of cop2 frorn tile losdiw point to tho prop,nration plant of bitu~i- nnus-cod strip mlncc to a;~to~lzcd. h,71Jlr.:~. The qrostion has arisen rrhethcr this is alwqvs econ~nicd, rxcl the purpcrse or' tnf s investigation is to de- termine, if possible, the econonic limlt for ~~torieod had.we.]

Jan 1, 1938

By Albert L. Toenges

[During the past few years there has beer trend away from locomotive haulage of coal from the loading point to the preparation plant of bituminous-coal strip, miner to motorized. haulage. The question has arisen whether this is always economical, and the purposes of this investigation is to determine, if possible the economic limit for motorized haulage. The operators of strip coal mines and of open-pit ore mines have shown great interest in this problem, and it is thought that the findings of this investigation will. Provo helpful to them.]

Jan 1, 1938

The research described in this report was conducted under a cooperative research agreement between the U.S Bureau of Mines Twin Cities Research Center (TCRC), Cleveland-Cliffs Inc. (CCI), and three operations in Northern Michigan managed by CCI: the Empire and Tilden surface taconite mining operations, and the Central Shops maintenance facility. All of these operations are in or near Ishpeming, MI. The Human Factors Research Group at TCRC is responsible for designing, planning, and conducting the research, and reporting on the findings. This project was carried out in order to investigate the high prevalence of back injuries being experienced by workers employed at the three CCI Northern Michigan sites, In an analysis of Company accident records for workers employed at these sites, it was determined that back injury problems confronting the CCI sites mirror those confronting the entire mining industry.

Jan 1, 1994

By Joseph F. Davies

Along with the humanitarian need for preventing accidents the cost of injuries must be considered. As a means of bringing the facts concerning the prevalence of accidents in mining and their direct cost before the operating officials and others interested in accident prevention in the mining industry, the United. States Bureau of Mines ha as recently made studies and published reports dealing with these subjects in several States 4. This report gives available data on the causes and direct costs of accidents in Virginia coal mines for the 4-year period 1929 to 1932, inclusive. Mounting compensation costs and insurance rates resulting from mine injuries indicate the necessity of measures to decrease the number and severity of accidents. These direct costs, as well as additional losses of an indirect nature, can be eliminated from the cost of production to the extent that accidents are prevented or reduced in severity.

Jan 1, 1934

By C. M. K. Boldt

Between 1989 and 1991, the greatest number of accidents in surface coal and metal/nonmetal mines involved haulage trucks. In 1995, the most frequently cited factor contributing to the 100 fatalities in these mines was powered haulage. In 1996, over 50% of the 84 Fatalities in mining that year were in surface mining. Because some of the world's largest mobile equipment is used in surface mines, and this equipment is involved in so many accidents and fatalities, new technologies are needed to alert truck drivers and people in spaces around the truck to the possibilities of collisions.

Jan 1, 1999

By Daryl R. Tweeton

The Bureau of Mines is investigating possible applications of geophysics to monitor leachate during in situ mining. Tomographic reconstruc-tion of seismic or electromagnetic crosshole data appears applicable. The tomographic program BOMTOM (Bureau of Mines tomography) was written and then used to investigate reconstructions with synthetic travel time data. The calculations confirmed that without constraints, crosshole data do not provide unique solutions. The solution is not determined solely by the data, but is also influenced by the velocity guesses starting the iterative solution procedure. The effectiveness of constraints in combatting nonuniqueness was examined. The requirement that the velocity not vary laterally at the top and bottom of the pixel grid was effective. This constraint is realistic when the top and bottom of the grid represent dry and saturated re-gions, respectively. Limiting the maximum velocity improved reconstructions, but may not be applicable in practice. BOMTOM uses the simultaneous iterative reconstruction technique (SIRT) with straight ray paths. The program is efficient in use of memory, and can be run on a personal computer. A source code in FORTRAN is listed. A source code in BASICA and compiled executable codes in both languages are available from the Bureau's Twin Cities (MN) Research Center.

Jan 1, 1985

By Alice M. Chieruzzi

This Country Documentation Report presents the development of economic indices for the Philippines for the period from 1970 through 1981. The work was done through the Bureau of Mines, Minerals Availability Program, under Contract number J01225001. This contract calls for the development of twelve index time series describing factor input costs in the mining sector of 95 countries. The twelve index time series describe the costs of: 1) mining wages, 2) construction wages, 3) equipment and repair parts, 4) bits and related steel, 5) eimber and lumber, 6) fuel, 7) powder and balsting agents, 8) tires, 9) construction materials, 10) industrial materials, 11) transportation, and 12) electrical power. These indices combined with weight factors being developed by the personnel of the Minerals Availability Field Office (MAFO) of the Bureau of Mines in Denver, Colorado, will be used to perform instantaneous updates of all costs relating to the mining industry. The indices were developed primarily for use in the Bureau's Minerals Availability Program in assessing the worldwide availability of nonfuel minerals.

Jan 1, 1983

By C. W. Davis

This is the first of a series of papers being; prepared as the work progresses in a study of the hydrometallurgy of manganese. The investigation is being made in an endeavor to make possible the utilization of lour-grade domestic manganese ores. The value of a hydrometallurgical process for manganese depends on the present and future uses for manganese products.

Jan 1, 1930

By B. M. Stewart

Researchers at the U.S. Bureau of Mines conducted a long-term groundwater monitoring and site characterization program at an abandoned 10-ha, acid-producing, copper-gold tailings impoundment in north-central Washington State. The purpose was to investigate contaminant release and transport, and attenuation mechanisms in the tailings, sediments below the tailings, and gravels downgradient of the impoundment. This report summarizes the monitoring results and physical properties of the tailings, the sediments below the tailings, and the groundwater system associated with the tailings. Water samples from the vadose and saturated zones of the impoundment were analyzed for 15 constituents. Concentrations of the same constituents were determined in water samples up to 3 m beneath the impoundment and in the shallow colluvium and deep bedrock at 76, 335, and 550 m downgradient and 168 m upgradient. Constituent concentrations within the tailings are quite variable and are influenced by pH, depth of oxidation, grain-size differential (surface area), hydraulic gradient, groundwater mixing, and the presence of hardpan layers, carbonaceous material, and organic matter. Most of the metal constituents decreased to background or near-background concentrations in the farthest downgradient well.

Jan 1, 2010

By N. S. Dalal, X. Shi, V. Vallyathan

"INTRODUCTIONThis paper summarizes our recent investigations of the potential role of silicon-oxygen based free radical species in the biochemical mechanism of the lung injury caused by the inhalation of freshly fractured silica. The impetus for this study came from the following observations. Inhalation of crystalline silica is associated with the development of acute and chronic silicosis. Chronic silicosis is characterized by the development of sharply marked concentric fibrotic nodules in the lung. This occurs over a period of several decades with the development of progressive respiratory impairment. In contrast, acute silicosis is manifested by the filling of the alveoli with an amorphous lipoproteinaceous exudate within a short period after exposure, and rapid development of respiratory disability often leading to fatality. Most studies on the pathogenesis of silicosis have focused on the elucidation of cellular mechanisms of cell injury and the development of chronic silicosis. Because pulmonary responses to crystalline silica are distinctly different for · the acute and chronic silicosis, we hypothesized that the acute response is associated with some unique properties of ·freshly formed silica particle surfaces, due to the formation of some reactive chemical species caused by the rupturing or the silicon-oxygen bonds. In occupations involving drilling, tunneling and sandblasting operations acute silicosis can be correlated with this unique surface reactivity of silica. The formation or reactive species was demonstrated, using electron spin resonance (ESR) spectroscopy (Dalal et al., 1986; Fuibini et al., 1987; Hochstrasser and Antononi, 1972). Grinding of quartz crystals under ultra high vacuum (10-10 torr) leads to the formation of Si- and SiO• radicals and these radicals are quenched by exposure to air and other gases (Hochstrasser and Antonini, 1972). ESR signals have also been reported from micronized quartz samples that were evacuated at 413 K (Bolls et al., 1983). In order to find a more direct relationship of such radicals to acute silicosis, we made ESR measurements on quartz dusts freshly ground in ambient air and found- that indeed grinding under ambient environment leads to the formation of the Si• and SiO• type of radicals which decay on storing the dusts in air or in biological buffers (Dalai et al., 1986; Vallyathan et al., 1988). The Si• and SiO radical formation on grinding has also been reported by Fubini et al. (1987). In addition, we recently found that •OH radicals are generated in aqueous suspensions of freshly ground quartz (Dalai et al., 1988; Shi et al., 1988; Vallyathan et al., 1988). We have subsequently carried out detailed cytotoxicity and biological assays on freshly made as well as aged quartz dusts. As summarized below, the results provide new insight into the biochemical mechanism of acute silicosis."

Jan 1, 1988

By Floyd G. Anderson

The Federal Bureau of Mines promotes the use of safe and effective dust-collecting devices for rock drilling in coal mines. To insure that such devices are available to the coal-mining industry, the Bureau issues certificates of performance for dust-collecting systems and certificates of approval for dust collectors and rock drills or other mining equipment with integral dust-collecting systems that meet the requirements of an established Schedule.4/ Investigations are conducted under the provisions of the current revision of this Schedule by engineers of the Branch of Health Research. This circular describes briefly the requirements and procedure for obtaining certificates of performance or approval and lists equipment that has been certified as permissible under Schedule 25 or its revisions as of January 31, 1961. The names and addresses of companies to which certificates have been issued are listed alphabetically at the end of this circular.

Jan 1, 1961

By Joseph J. Wallace

1. The Pittsburgh is the most important bed in Washington County from the standpoint of present production and recoverable reserves. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 short tons per acre-foot of coal in place, are estimated at 4,181 million short tons as of January 1, 1954. Of this total, 4,132 million short tons is in beds 28 inches and more thick. Areas in some beds 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.

Jan 1, 1955

By A. F. Colombo

The western Mesabi range nonmagnetic taconites containing about 34 percent Fe were evaluated by the Bureau of Mines in a 900-pound-per-hour pilot plant employing a selective flocculation-desliming-cationic flotation technique. The flotation step was a reverse flotation process and involved the flotation of the gangue minerals. The objective of the research was to increase the availability of domestic raw materials for the iron and steel industry. The beneficiated ores yielded concentrates containing 62 to 64 percent Fe and less than 5.5 percent Si02 with accompanying iron recoveries that averaged about 75 percent. Comparable flotation results were obtained with either fresh or 80 to 90 percent reclaimed water. Recycled waters having turbidities as high as 5,000 ppm Si02 did not affect the flotation process. Reclaimed waters containing residual calcium contents of less than 10 ppm gave better flotation concentrates than those containing 15 ppm.

Jan 1, 1976

By William J. Douglas

This document describes the development of a conventional mining equipment data base, and an approach for conducting industrial engineering studies of arbitrary mining systems employing network techniques. Data was acquired through underground time studies. Each member of a four-man field team was assigned to a specific machine during each shift for which observations were conducted. Using digital wrist watches and networks describing the man-machine interactions, all events occurring luring the course of each shift were recorded on cassette tapes. The tapes were transcribed, coded, keypunched, and validated using computerized editing techniques. The resulting data files were processed to provide statistics relating to activity durations and event frequencies. The results were used to evaluate operator, machine, and system performance for each section which was observed. Equipment, reliability, and maintainability analyses were conducted using the industrial engineering data files in conjunction with historical information collected at the mine site.

Jan 1, 1976

By C. W. Smith

The Bureau of Mines conducted laboratory-scale beneficiation tests on a sample of corundum gneiss from Montana to devise a method for beneficiating corundum for use as a substitute for refractory-grade bauxite. A flotation process utilizing petroleum sulfonate as the collector in an acid circuit was devised. Results showed that two flotation schemes each produced a concentrate exceeding the national stockpile specifications for calcined bauxite. From a feed containing 28 pct corundum concentrates containing up to 92.5 pct alumina (A1203) were produced with a corundum recovery of 78.5 pct.

Jan 1, 1987

By J. F. Smith

A series of studies of emissions from large coal-fired steam generators have included measurements of the concentrations of oxides of sulfur and oxides of notrogen. The sampling equipment, method of sampling, and analytical techniques used for processing of these samples are detailed. A method based on the precipitation of benzidine sulfate was developed for determining both SO3 and total oxides of sulfur in the presence of interfering acidic components in the stack gases. In addition, difficulties encountered with sampling and analytical techniques are also described.

Jan 1, 1968