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By Almon F. Robertson

This report is one of a series based upon investigations made and being made within the Missouri River Basin in Montana by engineers of the Bureau of Mines , Albany Branch , Mining Division . These investigations are being made primarily to provide preliminary information to the Department of Interior agencies and to others concerned with planning the proposed Federal power developments within the Missouri River Basin. This report has been designed to permit public distribution of the factual data obtained . Virtually all known metallic -mineral occurrences and some nonmetallic mineral deposits within Fergus County were investigated in 1948. The investigations cannot be considered complete , however , because some long inactive mines or prospects may have been missed . Most of the old mine and prospect openings now are caved ; many are completely inaccessible . Many of the claims located years ago have been abandoned ; others have been relocated under different names and ownerships . Because of such conditions , much of the information regarding their development and operation necessarily has been obtained from available Federal and State publications , supplemented by information provided by owners and local residents .

Jan 1, 1950

By J. Venter

The history of firedamp is the same as that of coal: The initial stage was the accumulation of vegetation, which was converted into peat under certain local conditions, then lignite, bituminous coal, and finally anthracite. These deposits ceased to increase owing to inundation that deposited earthy sediment, sometimes as much as several tens of meters (several tens of yards). The vegetable matter, whether it was covered with sediment or not, began to ferment. The basic organic components of the vegetable matter are: Cellulose, lignin, and wax and resin in varying proportions, according to the different kinds of vegetable matter. There are, in addition, some impurities, generally mineral.

Jan 1, 1953

By Brian M. Harney

The technique of remote sensing, used for many years by earth scientists, is being applied to the detection and monitoring of air pollution. Instrumentation being developed is of a very diverse nature and is effective, Fn varying degrees, at ranges from 1,000 meters to the altitude of a space satellite. This paper describes a number of the recent developments in this new field. Instruments based on spectroscopic, laser, and photographic systems are discussed. Sensors are being developed which utilize correlation spectrometry, interferometry, Raman scattering, Mie scattering, laser line absorption, and simple photographic detection.

Jan 1, 1973

Researchers, medical organizations, statisticians, and others often use data on the nature and rate of occurrence of occupational diseases in directing their efforts and plans. Very often this information is developed from the reports of the States which describe the nature of work¬men's compensation claims and awards and the frequency with which they are made. To be meaningful, the statis¬tical information must be viewed in the context of the State laws involved. There is considerable variation among the laws of the different States. The Bureau of Mines has responsibilities for protecting the health of persons employed in the mineral industries and for the development of useful mineral products. To assist the Bureau in the accomplishment of its objectives, this compilation has been undertaken. For the benefit of the mineral industries, and any others who may have a similar interest, this volume is made available. An earlier compilation of the Bureau of Mines on this subject was published in 1952.4 However, during the intervening years, sufficient changes have been made in State laws to warrant completely recompiling the information. This publication includes the laws of the States, the District of Columbia, Puerto Rico, and the Virgin Is¬lands through 1964. Only those portions of the workmen's compensation laws which apply to or as ' related to occupational diseases are presented, and in each case enacted additions to and deletions from the basic law have been incorporated into the text of the law, thus snak¬ing it unnecessary to search out the various amendments made each year.

Jan 1, 1967

By F. M. Boler

The U.S. Bureau of Mines conducts research at the Galena Mine, Wallace, ID, with the aim of mitigating the effects of rock bursting. Destress blasting is commonly used as a stress control technique at the mine. A digital seismic array and an array of borehole pressure cells (BPC's) had been installed near the site of a stope undergoing mining and periodic de stressing. The instrumentation was being monitored at the time of a destress blast of the 46-99 stope. No significant seismic events occurred coincident with the destress. However, the destress was followed by a 2 ½ -week period of increased seismic activity, including two damaging events on February 7, 1990, at 034500 (hour, minute, and second) and 122020 Pacific standard time. BPC measurements indicated coseismic ground pressure changes on the order of 200 to 300 kPa associated with the damaging events. Fault plane solutions and dislocation models established that stress changes induced by the event at 034500 may have been significant in promoting the occurrence of the event at 122020. Theoretical investigations suggest that applying knowledge of the existing stress field, an understanding of rock burst mechanics, and fracture mechanics principles can improve destress effectiveness.

Jan 1, 2010

"A bed, British Columbia, Canada, coal, carbonizingproperties B 510Pa., coal, washing characteristics RI 4941A' bed, Pa., coal, washing characteristics RI 4834"

Jan 1, 1960

By William R. Hardwick

Present information indicates that a copper deposit can be safely fractured with a nuclear explosive and the copper successfully recovered by the in-situ leaching method. The process is not yet at the stage where it can be presented t ) the mining industry as a technique proven in all its aspects, but it is a method with high success potential. Unknown factors must be evaluated by a full-scale test before the economics or the extent of the use of the method by the mining industry can be predicted. Preliminary calculations indicate that the cost of fracturing a copper deposit nuclear explosives may range from l.8 to 55.2 cents per ton or in some case: less than a cent per pound of recoverable copper. Copper may be recovered at less cost than by conventional methods. Deposits with 4 pounds of recoverable copper may be economic and production from a deposit may begin in less than half the time required for conventional methods.

Jan 1, 1967

By E. H. Boyle

The Bureau of Mines has evaluated the potential availability of silver from 436 mines and deposits in 41 market economy countries (MEC?s) comprising five major economic categories of deposits: predominantly silver deposits and predominantly zinc, lead, copper, and gold deposits. This study evaluated the long-term cost and availability of primary silver production from 53 producing and 13 nonproducing predominantly silver properties in 11 MEC's and estimated the total recoverable silver from 370 properties as a coproduct or byproduct of zinc, lead, copper, or gold production. This study resulted in estimates of a demonstrated resource of 5.99 billion tr oz of recoverable silver as of January 1984. Of this total, 23.5 pet is in the 66 mines and deposits classified as predominantly silver properties. The largest quantity of recoverable silver, 43.9 pct, lies in the 121 properties classified as predominantly zinc, with 26.5 pct in 120 properties classified as predominantly copper, 4.1 pet in 21 predominantly lead properties, and 2.0 pct in 108 predominantly gold properties. At current silver prices, the economics of silver production favor silver that is a byproduct or coproduct of zinc, lead, copper, or gold, and much of the silver production in the United States from the predominantly silver mines is at an economic disadvantage in comparison with silver production in other countries.

Jan 1, 1986

By J. S. Hansen

To advance technology that can conserve critical materials, the Bureau of Mines investigated a cast-on hard-surfacing that wear resistance and confines alloy additions to wear-prone surfaces. Wear-resistant material in form is on a polystyrene , the is embedded in a mold of unbonded s and the wear-resistant material is transferred to a cas surface at the time of For low-stress abrasion, derived from high-carbon ferro-chrome had higher wear resistance than did commercially available weld-hard. The microstructure of the was typi-white iron carbides. Free carbon added to the ferrochrome powder produced more M7C3 carbides than did material contained in surfacings made from ferrochrome alone, and improved the wear resistance. Several white iron powders with greatly reduced chromium contents also white iron contain-M7C3 carbides. One derived from white iron powder had wear resistance to that of weld-deposited hard facings. Among the parameters investigated, surfacing thickness was found to have a or influence on diffusion of elements out of the , microstructure, and wear resistance. The results of field tests on bucket-wheel excavator teeth and plowshares with cast-on hard surfacing are given.

Jan 1, 1985

By BUREAU OF MINES

Mercury has been used by mankind since prehistoric times. It has been, and is now, widely used in industry and medicine and has unique properties which make direct substitution difficult or impossible. At present its prin- cipal uses are for electrical apparatus, control instruments, electrolytic soda preparation, mildew-proofing paints, pesticides, and medical and dental preparations. Deposits of mercury are less common than those of other base and precious metals, but some of the deposits are very large and have been ample to meet the world's past demands. The price of mercury has had many sharp fluctua- tions, but in general, the limited number of producers has resulted in a more stable price structure than that of many other commodities. The United States has been one of the main producers of mercury, and from 1850 to 1961 produced 3,247,704 flasks. Yearly production since World War II has varied from 4,535 to 38,067 flasks. An estimate of domestic resources of mercury producible at various price ranges was prepared for each mercury mine by combining specific knowledge of mercury mineralization with estimates of potential, based on geologic informa- tion and past production history. The sum of the individual estimates for each price range is shown in a table. A parallel estimate of nationwide production potential was made from a study of past price and production relationships. These were analyzed by plotting yearly production figures against the previous year's price, expressed in dollars of constant purchasing power. An equation was fitted to the data by mathematical means and was used to extend the curve into areas of higher than historic prices. Potential production rates at various price levels were taken from this graph. The estimated yearly production rates were used to make an estimate of total potential based on the premise that produc- tion rates and reserves have a proportionate relationship.

Jul 1, 1964

By W. W. Agey

As a part of the program of investigation of domestic sources of manganese in the western United States, engineers of the Bureau of Mines examined. and obtained samples of ore from two properties in the vicinity of Barstow, San Bernardino County, Calif. In addition to these, samples from two other properties in the same vicinity were submitted by the owners. As the ores were too low-grade to be acceptable for the direct production of ferromanganese, beneficiation studies were made to determine the amenability of the ores to concentration by ore dressing. The Big Reef manganese claims axe about 140 miles east of Barstow, Calif. The claims were leased by W., E. Thurber of San Gabriel, Calif., from the owner, C. S. VanDoren of Daggett., Calif. Manganese oxides occur as a replacement deposit in heavily brecciated andesite along a fault plane. Four samples were taken by an examining engineer of the Bureau of Mines from the ore zone, which, when composited, were representative of all the exposed ore. Preliminary tests were made on lot B, and final tests wore made on the composite sample. The Trans-Oceanic property is about 20 miles southeast of Barstow, near Newberry, in the. Pisgah mining district, Calif. The sample, submitted by the owners, was taken from a 1,000-ton reject clump from a hand-sorting operation. The ore occurs as a replacement of rhyolite.

Jan 1, 1952

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

The number of railroad coal cars (open top hoppers), dominated rail car orders and deliveries in 1975 according to announcements made February 11, by the Association of American Railroads and the American Railway Car Institute. Acting to keep ahead of increased coal production, the railroads installed 21,748 new coal cars in 1975, the most since 1957. The 1975 installation resulted in a net increase of 6,560 coal cars and an overall gain of 4.5 percent in the total capacity of the hopper car fleet. With most of the new coal cars going into unit train service --where car utilization is greatest --the railroads actual coal-carrying capacity was increased far more than 4.5 percent. The AAR estimated that unit train operations now move 50 percent of all rail-hauled coal compared to only 42 percent 2 years ago. COBALT - The Societe Miniere de Tenke Fungurume (SMTF) copper-cobalt project in Zaire reportedly was suspended in January for an indefenite length of time. According to officials, the deferment resulted from a number of adverse factors, one of which was exceptional increases in capital costs. The project was scheduled for completion in early 1978, with an eventual production of 14.3 million pounds of cobalt per year. Reserves of cobalt were reported to be 505 million pounds. SMTF is a consortium and includes American, British, French, Japanese, and Zairian interests.

Jan 1, 1976

By Heber E. Peterson, Sill. Claude W.

"INTRODUCTION In the usual volumetric determination of uranium, the solution containing uranium is reduced in a Jones reductor, yielding a mixture of trivalent and tetravalent uranium; the trivalent uranium is oxidized to the tetravalent state by bubbling a stream of air through the solution. The resulting solution of tetravalent uranium is titrated with a standard oxidant, generally sulfatoceric acid, dichromate, or permanganate. It seemed likely that the same general procedure could be used in determining semimicro quantities pf uranium if the conditions affecting the variables involved were understood more clearly than at present. In the method described below, the use of ferric sulfate to oxidize tetravalent uranium allows the titration to be made at room temperature in an essentially colorless solution with sulfatoceric acid. The latter oxidant in turn permits the use of the very stable indicator, ferroin; with its sharp color change and exactly reproducible blanks.Solutions of uranyl sulfate were prepared by diluting a stock solution that had been standardized gravimetrically according to the method of Lundell and Knowles (8).3/ Solutions of sulfatoceric acid were prepared according to the directions of G. F. Smith (12) and were standardized against arsenic trioxide in the presence of osmic acid according to the directions of Glen (5). The cerium solutions were stored in 18-liter carboys fitted with siphon arrangements so that the bottles did not need to be opened and protected from light in a dark cupboard. Under these conditions, even the 0.01 N solution changed by less than 1 part per thousand over a period of about 6 months."

Jun 1, 1952

Research 84 highlights significant studies conducted during the past fiscal year at Bureau facilities and offices. Readers who want more information about the projects and studies summarized here can contact the researchers whose names and locations appear with each summary. General information on Bureau of Mines programs is available from the Office of Technical Information, 2401 E Street, NW., Washington, DC 20241. A listing of principal officials, a location map of field facilities, and a selected bibliography of publications and patents issued on Bureau developments during the past 3 years are provided.

Jan 1, 1984

By L. H. Harrison

In coal mines equipped with electrically driven mechanical mining equipment, the problem of protection for electrical circuits and machinery important, because the hazards of fires and explosions resulting from electrical failures is greater than in most other industries. There is need for better methods and improved protective devices for this service. Studies and tests designed to determine possible value of the short-circuiting contactor as an electrical device for coal mine service were investigated. Preliminary made to determine the operating characteristics of the device, after which tests were made under actual service in three coal mines. Ordinarily, electrical protection in coal mines is divided into three classes, as follows: 1. Overload protection that is intended to protect against damage from overheating and excessive mechanical strain due to overloading. 2. Short-circuit protection that provides a means of de-energizing the equipment instantly when an accidental short circuit occurs in the equipment or on the power system. Short cm protection tends to damage from fires and, explosions resulting in the dissipation of large amounts of electrical energy in a short circuit. 3. Ground fault protection that, in its various forms, is intended, to maintain the frames of electrical equipment at or near the same potential surfaces in contact with the earth for the purpose of safe-guarding human life.

Jan 1, 1951

By Frank Cook

In this two-year study, an evaluation of mining and reclamation practices at 159 randomly sampled surface coal mines in the United States was conducted. It is concluded that reclamation practices in most of the 22 coal-producing states were adequate during 1975, but that improvement in reclamation performance was desirable in the acid area of the central U. S. and in mountainous southwestern Virginia. Productivity improvements should result from research to determine efficient or optimal operating procedures for dragline stripping of single and multiple seams, surface mining of lignite, multicut and multiseam haulback mining on steep slopes, mountaintop removal, and surface mining in swampy or deeply glaciated areas. Specific candidate research projects are discussed in this report.

Jan 1, 1976

By Richard E. Thill

The Bureau of Mines' Oil Shale Data Bank (OSDB) was created in 1976 to serve as a centralized source for the storage, retrieval, and dissemination of technical literature, patents, and information on research projects in oil shale. Thousands of bibliographic references, patents, and research projects relating to the mining of oil shale have been identified, abstracted, and indexed according to selected keyword topics. The resulting data bank listings are contained in three sections, each with a separate keyword breakdown for use in rapidly identifying references pertaining to a specific subject. All references cited in the OSDB were published prior to an established cut-off date of May 1, 1981, when a redirection of Bureau of Mines programs resulted in the loss of project funds and the subsequent phasing-out of data bank operations. ACKNOWLEDGMENTS The oil shale data bank listings are the result of a team effort of the project staff. The contributions of Jimaleen Jansma for keypunching, information acquisition, and data entry, and John Brandenburg and Sandra Brake for keywording and information acquisition are gratefully acknowledged. Appreciation is expressed to the staff members of the Smithsonian Science Information Exchange, Washington D.C. for their cooperation in supplying data on recent research projects in oil shale for inclusion in the OSDB listings. Appreciation is extended also to the staff of the Gallegos Research Group for assisting with computer services to obtain the final printouts and transfer of files onto magnetic tape.

Jan 1, 1982

By K. E. Stanfield

This report presents the results of analytical studies made on two series of oil-shale samples from the Mahogany ledge of the Green River mine the character of the various grades of oil shale that are being mined and processed into shale oil and refined products at the Bureau of Mines Oil-Shale Demonstration Plant at Rifle, Colo. The analytical work was part of a synthetic liquid fuels program being conducted at the Petroleum and Oil-Shale Experiment Station, Laramie, Wyo. The 16 oil shales ranG6d in color from a gray brown ( or a sample that assayed 10.5 gallons of oil per ton to a very dark brown for a sample that assayed 75.0 gallons of oil per ton. In general, the samples were similar as to the types of organic and inorganic matter that they contained but varied widely in the amounts or these constituents. The principal constituents were calcite, dolomite, illite, and yellow organic material, while the minor constituents were quartz, feldspar and plagioclase feldspar, pyrite, marcasite, analcite, opal, black organic material, and small woody fragments. Some micro-fossils, spores and pollen grains were found also.

Jan 1, 1951

By Walter K. Utt

The process of drilling and bolting the roof is currently one of the most dangerous jobs in underground mining, resulting in about 1,000 accidents with injuries each year in the United States. To increase the safety of underground miners, researchers froth the Spokane Research Laboratory of- the National Institute for Occupational Safety and Health are applying neural network technology to rite classification of mine roof strata in terms of relative strength. In this project, the feasibility of using a monitoring system on a roof drill to assess the integrity of a mine roof and warn a roof drill operator when a weak layer is encountered is being studied. Using measurements taken while a layer is being drilled, one can convert the data to suitably scaled features and classify the strength of the layer with a neural network. The feasibility of using a drill monitoring system to estimate the strength of successive layers of rock was demonstrated in the laboratory.