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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

By Frank K. Cameron

"The DepositsThere are two large deposits or groups of deposits of potash salts which, at the breaking cut of the great world war in 1913 and for several decades preceding, were practically the only commercial sources of supply for the entire world. In both cases the origin of the deposits was sea water, the potassium salts being deposited by desiccation, but there were modifying factors which were not entirely the same in both cases so that well defined and important differences exist in these deposits. The larger and better known group, called the Stassfurt Deposits, are in Germany in the region about or adjacent to Magdeburg and Halberstadt. The general character of these deposits and the methods for recovering potash from them have been frequently described, not only in technical publi¬cations, but in the non-technical propaganda long maintained by the Kali Syndikat, an organization founded on a ""cartel"" with the supervision and support of the late Imperial German Government.Less well known are the smaller though nevertheless extensive deposits in the neighborhood of Mulhouse in Upper Alsatia, which were also under the control of the Kali Syndikat at the breaking out of the war but have now passed to French control, with the reentrance of Alsace into the French Republic.The Alsatiaa deposits, while less extensive than the German deposits, are, nevertheless of great magnitude. They occupy a large part of the area between the Vosges Mountains and the River Rhine, from Col¬mar on the North to Mulhouse on the South. Indeed a few borings on the East bank of the Rhine indicate that the deposits may extend under the river and to some distance beyond Buggingen Linken, Baden, though it has not been Shown as yet that this extension is of commercial significance.As is well known, the Stassfurt potash occurs as potassium chloride or potassium sulphate or both salts, intimately mixed with salts of sodium, magnesium eau& calcium (lime) and contaminated with substances. insoluble in water such as ferric oxide, clay etc. The potash salts are segregated in more or less extensive 'pockets' throughout the salt mass, these segregations departing usually from the horizontal. But the main ""potash region"" is a stratum varying from 30 to 150 feet in thickness and at a depth requiring shafts 5000 feet."

Jul 1, 1919

By Steven R. Davis

Voyageurs National Park in northern Minnesota, and a 30-mile radius area of influence on the United States side of the International Border, was examined for hardrock (nonferrous metallic minerals and diamonds) mineral potential and environmental sensitivity by the U.S. Bureau of Mines. The investigation also included an analysis of current Metallic Minerals Leasing Rules of the State of Minnesota, and the probable effects of changes proposed to the current rules by the State of Minnesota in order to "encourage mineral exploration and development." The study has determined that the proposed changes to the Minnesota State Leasing rules will have minimal, if any, impact on the likely, foreseeable levels of mineral-related activities in the State as a whole, and particularly, in the area of influence to the Park. Voyageurs National Park management was advised on the extent and character of the proposed rules changes, and on those items of concern meriting a specific and timely response by the National Park Service.

Jan 1, 1994

By J. E. Hipp

Three electrostatic field sensing proximity warning devices were tested using full-scale cranes and power line systems, a scaled model facility, environmental testing facilities, and theoretical/numerical analysis. The design objective of each device is to assist in safe crane operation near overhead power lines. Several design deficiencies (varying from device to device) were observed, including inadequate overlap in sensitivity ranges, utilization of vacuum tubes and electro-mechanical parts, temperature sensitivity and inaudible alarms. In addition, the testing showed major device limitations including sensitivity to boom orientations and length, polarization dependent responses, and unreliable operation in the presence of multiple power line circuits. The multiple power line circuit problem is intrinsic to electrostatic sensing devices. The remaining deficiencies and limitations are correctable within a state-of-the-art design. This investigation is not intended to evaluate the safety aspects or policy of utilizing proximity warning devices. Rather, the purpose is to determine the performance characteristics of such devices in relation to the criteria specified in proposed MSHA regulation 77.805-4 (i. e., the devices must alarm at a distance of 10 feet from the power line).

Jan 1, 1980

By Albert L. Toenges

This report is the second of a series describing methods and systems of mechanical mining; where operations are conducted on more than one shift. The first report, Information Circular 7014,4/ describes mining operations at 14 mines and the present paper describes operations at 11 additional mines. The purpose of this study is to analyze the advantages and disadvantages of the various types of equipment and mining systems now used where more than one shift is worked per day. Physical conditions vary in different and in the same mining districts and determine, together with economical considerations, the systems of mining and the types of mechanical loading equipment to be used. The information presented in this paper may be helpful to operators or others who may contemplate installing a mechanical mining system. The equipment used in the mines described comprises conveyors, scrapers, mobile loaders, mobile conveyors, and combination of these types. The description of the mining systems and practices at the mines investigated is detailed only as they relate to and affect mechanization. In computing the operating data in mines that are not totally mechanized, employees not working directly on production have been charged to output from mechanized sections in proportion to the percentage of mechanization. The operating data for comparing various systems are for an average working dry, as the number of men working on idle days varies greatly in different mines.

Jan 1, 1939

By F. E. Cash

The Holmes Safety Association was organized and named in honor of the late Dr. Joseph A. Holmes, first director of the United States Bureau of Mines. The association is a national organization and operates through local, sectional, or State chapters in mining, petroleum, and allied industries. The National Council of the Holmes Safety Association consists of representatives of State councils and local chapters, with the Director of the Bureau of Mines as president.

Jan 1, 1929

By W. W. Adams

The accident-prevention record of the coal-mining industry in the United States was more favorable in 1936 than in 1935, both from the standpoint of the relative safety of the individual miner on the job and of the price in life and limb that the Nation paid for its year's supply of coal. The increase in relative safety of the individual miner was indicated by a lower death rate and a lower injury rate than in the preceding year per million man-hours of exposure to the hazards of mining; that is, per million hours of work performed by the employees. (See table 1.) A reduction in the price in life and limb that the Nation paid for a year's supply of coal was indicated by a smaller death rate and a smaller injury rate per million tons of coal produced. Thus the individual miner was a better insurance risk, as far as accidents were concerned, in 1936 than in 1935, and a ton of coal used in the homes and industries of the country represented less human suffering than in 1935. The two points of view are distinct, and both should be kept in mind when considering accidents and safety in coal mining or in other industries. More men were employed in 1936 than in 1935, and more workdays were available for the individual miner. Large gains were also made in the total number of man-shifts and man-hours worked in the industry as a whole. In number of tons of coal mined, 1936 showed large gains over 1935. Moreover, the average output of coal per man-hour worked was higher in 1936 than in 1935. All of these gains were made without lengthening the average number of hours of work per man per day.

Jan 1, 1939

By T. G. Chapman

This paper has been abstracted from a forthcoming Bureau of Mines bulletin on the concentration of copper ores in North America. GENERAL DEVELOPMENTS IN CONCENTRATING COPPER ORES FROM 1912 TO 1932 During the east 20 years the milling of copper ores as practiced in the larger concentrators has chanced to such an extent that comparatively few of the machines in use at the beginning of this period remain in service today. Concentrating Practice in 1912. In 1912 the usual equipment for concentrating copper ores comprised jigs for the coarser sizes, tables and sand vanners for the intermediate sizes, and vanners for the finer crushed and ground material. Rolls operated in series under graded crushing conditions, were in common use for the liberation of the copper minerals; grinding by Chilean or Muntington mills ordinarily was confined to the coarser tailings of jigs and tables.

Jan 1, 1934

By Julie N. Walker

This U.S. Bureau of Mines report reviews the first 2 years of the agency's progress in implementing total quality management (TQM), which the agency refers to as Quality Improvement (QI). All employees have been trained in basic TQM concepts, a cadre of facilitators has been selected and trained, and 13 Bureauwide teams are addressing specific issues that were identified by Bureau employees nationwide as problem areas. Also in place are a Quality Council composed of the Bureau's top executives, a Quality Management Board, and eight QI Working Groups to provide a national 01 infrastructure. There are also Quality Steering Groups at each Bureau location nationwide to address local concerns. In addition to the narrative text, the texts of salient memoranda and other documents are included as appendixes.

Jan 1, 1992

By Linda L. Chasko, Charles P. Lazzara, Gary Braselton, Ronald S. Conti

Preparedness is an important element of any underground mine's strategic plan in dealing with an unexpected event, such as a fire. A fully implemented fire preparedness and response plan is essential in reducing the probability and seriousness of a mine fire. This report describes the development of an underground coal mine fire preparedness and response checklist (MFPRC). The checklist is a data collection instrument for profiling both the fire prevention and response capabilities of a mine site and usually requires 3 to 4 days to complete. The checklist encompasses conditions, procedures, and equipment that have frequently been identified as the primary or contributing causes of underground coal mine fires. At least 1 day is needed underground to evaluate the water system. This entails measurements of water flows and pressures at fire hydrants, and water throw distances of fire hose and nozzles at several locations (mains and branch lines). A few of the other topics that are discussed with mine personnel include detection and suppression systems, combustible materials, mine rescue and fire brigades, and firefighting equipment. The MFPRC was developed by the National Institute for Occupational Safety and Health (NIOSH),Pittsburgh Research Laboratory. Under a Cooperative Research and Development Agreement (CRADA) with Cyprus Amax, Twenty mile Coal Co. (Oak Creek, CO), the checklist was field tested and further refined. Additional field tests were conducted at several other operating coal mines.

Jan 1, 2000

By Chas. F. Jackson

This bulletin is one of a series of Bureau of Mines reports dealing with mining methods, practices, and costs. A study of this subject was undertaken by the Bureau in cooperation with a large number of mining companies in 1928. This study continued for 5 years, during which engineers of the Mining Division of the Bureau visited most of the larger mines and many smaller ones in the United States, as well as several mines in Canada and Mexico. As a result of this study, 75 reports dealing with underground mining methods and costs at different mines were published as information circulars. Circulars also were issued on 6 open-pit mines and 2 gold-dredging operations. These circulars were written by the managers, superintendents, and engineers in charge of the operations, in some instances in collaboration with Bureau engineers. They were prepared according to a standard outline drawn up by the Bureau to obtain uniformity in textual treatment and in the arrangement and basis of setting up cost and operating data.

Jan 1, 1936

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

Jan 1, 1960

In 1990, the Bureau of Mines (BOM) conducted a mineral investigation of the mines and prospects in the East Mojave National Scenic Area (EMNSA), San Bernardino County, California During field work, BOM identified 701 mines and prospects in EMNSA for which the geology, mineral resources, and mining history were compiled and summarized. Analytical results for 1,188 rock samples collected are tabulated. Total value of identified resources in EMNSA is $5.0 billion. Twenty-four mines and prospects were deemed profitable under current economic conditions. Development could generate considerable economic benefits to San Bernardino County. Potential economic benefits from mining the deposits were evaluated under the following access restrictions for EMNSA: 1) full access, 2) HR 3460, and 3) S 11/HR 780. Under the full access scenario, cumulative mine revenues are $3.0 billion, cumulative personal earnings at mines and supporting industries are $0.94 billion, and annual jobs at mines and supporting industries are 2,379. Under HR 3460, mine revenues, personal earnings, and annual jobs are $2.9 billion, $0.88 billion, and 2,165, respectively. Under S 11/HR 780, mine revenues, personal earnings, and annual jobs are $1.0 billion, $0.32 billion, and 936, respectively.

Jan 1, 1990

By Peter Grandone

"INTRODUCTION The injection of water into partly depleted-oil-bearing formations as a means of supplying additional energy to flow oil wells now is recognized by the petroleum industry as an effective method of increasing the recovery of oil. The benefits to be derived from water-flooding oil sands were discovered accidentally more than 4o years ago, when oil producers in the Pennsylvania and western New York fields observed suustantial increases, in oil-production rates when water leaked past corroded casings of old wells into producing sands. This observation prompted some operators purposely to perforate or slit the casings opposite the producing formation in some of their wells to permit water to enter the formation. However, as many operators viewed the practice with skepticism and considered it to be in violation of oil-conservation principles,- systematic water-flooding was not initiated until the Pennsylvania legislature, in 1921, enacted a law authorizing water-flooding of oil sands in that State.Although water-flooding has been practiced in a haphazard manner for more than 25 years in Chautauqua and Montgomery Counties, Kansas, planned or systematic water-flooding in that State had its inception in 1935, when the legislature, following the example of Pennsylvania, also passed a lava/ authorizing water-flooding. The early operations and, to some extent, those still, practiced in the Chautauqua-Montgomery area consisted in raising or perforating the casing to allow water from upper strata to gravitate into underlying oil-producing formations. The extent to which this type of water-flooding affected petroleum production in the old stripper area of eastern Kansas is not known, but it is known to have increased oil production ap¬preciably from many leases.Following enactment of the law permitting water-flooding in Kansas, three operators inaugurated, in that same year, three organized flooding projects in three different counties of the southeastern part of the State. The first organized project on record was that of the York State Oil Co. in the Seeley pool, Greenwood County. On this project, the injection was started on May 15, 1935, into the Bartlesville sandstone at a top depth of 1940 feet."

Jul 1, 1944

By W. W. Adams

Every man-hour of work performed in and about the coal mines of the United States had a 2-percent heavier death load from accidents in 1938 than in 1937. This is an unorthodox way of stating that the death rate per million man-hours of exposure or employment was 2 percent higher in 1938 than in 1937, increasing from 1.74 to 1.78. Thus the average miner had a 2-percent greater chance of being killed in 1938 than he had in 1937. The average quantity of coal resulting from 1 man-hour of work increased 3.6 percent -from 0.615 ton in 1937 to 0.637 ton in 1938. The production of the average ton of coal was accompanied by a slightly smaller loss of life in 1938 than in 1937, the accident rate being 2.793 per million tons in 1938 compared with 2.833 in 1937.

Jan 1, 1941

By Raymond B. Ladoo

The uses for which ground talcs are suited closely depend upon their physical and chemical properties , but , in spite of this fact , little scientific investigation has been made in order to devise quick and accurate tests for the determination of these properties . The chemical properties of talc are inherent and may not be altered or modified except by selective mining or by chemical processes not practical in the present status of the industry . However , the determination of chemical properties is not so important , for most uses , as of physical properties , although sometimes certain chemical characteristics are perhaps unduly insisted upon by chemists in some industries . Physical properties are dependent both upon mineralogical characteristics and upon methods of grinding and sizing and may thus be partly changed or modified by changes in practice . There is so little known of the chemistry and physics of the various processes in which talc is used that the purchase and sale of talc is governed more by rule- of- thumb methods dependent upon individual opinion and often , prejudice , than by accurate , standard tests . This not only causes unwarranted price fluctuations , but injures both the producing and consuming industries by creating false ideas of the suitability of talc for various uses . It thus seems important that present tests be standardized and made uniform for the whole industry , and that new tests devised to fill the existing gaps .

Jul 1, 1920

By M. Vanpée, H. G. Wolfhard

Jets of hot gases issuing into explosive gaseous mixtures are efficient agents of ignition . The ignition temperature is defined as the temperature of the jet as it enters the cold explosive mixture which is just high enough to produce ignition . Such data have been published recently.5/ The investigators note especially that no correlation seems to exist between hot - gas ignition temperatures and spontaneous ignition temperatures , although there is a rather loose relation with limit flame temperatures . Before a more quantitative theory of the hot - gas ignition process can be attempted effectively , several questions must be answered : ( 1 ) Can the reactions leading to ignition be described by an Arrhenius type activation energy? ( 2 ) Is ignition preceded by an induction period ? ( 3 ) What is the rate - determining process of the ignition ? (4) And how does turbulence affect this type of ignition ?

Jul 1, 1960

By John Wilson

This report describes the performance of Phase I of a project to design, analyze, and demonstrate a multilift longwall mining method applicable to mining coal seams twelve (12) feet or more in thickness. A non-simultaneous multilift operation is the most viable thick seam mining technique for introduction to the United States coal industry. In the case of the proposed site at Emery, Utah it will result in an increase in coal extraction from 30% with present methods to at least 50% and possibly more. The major technological advance involved in this project is mining a lower lift under a previously mined upper lift. To accomplish this, entries must be developed and maintained beneath the upper lift gob. This will necessitate the use of steel supports at frequent intervals throughout the lower lift' entry system. This has not been done in the U.S. to date. An economic analysis of the project indicates that, while this method will result in a higher than average cost per ton for coal mined, the coal would be competitive with current-operation in the area.

Jan 1, 1976

This report presents information developed during Bureau of Mines contract H0242016, "Mine Shaft Fire and Smoke Protection Systems" from May, 1974 through June, 1975. Purpose of the metal and nonmetal health and safety project was to evaluate mine shaft fire and smoke hazard problems, and to develop and demonstrate a low-cost, reliable mine shaft fire protection system that would protect against such hazards and would be applicable to a majority of metal and nonmetal mine shafts, including raises and winzes, especially in deep mines. Program effort proceeded through five phases, culminating in the successful in-mine fire demonstration of a prototype system. In addition to this final report, a film is available which depicts components of the system and its successful shaft fire testing at an underground mine.

Jan 1, 1975

By E. P. Youngman

This paper presents one of a series of digests of foreign mining legis- ation and court decisions that is being prepared in advance of a generel report elative to the rights of American citizens to explore for minerals and to own nd operate mines in various foreign countries. This interpretation of the laws of Demark and her possessions, has been prepared entirely from answers made by Ernest L. Ives, American charge d'effaires, Copenhagen, to a questionnaire ini- isted by the United States Bureau of Mines and transmitted through the courtesy of the Department of State.

Jun 1, 1932