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By A. D. McMahon

This survey is one of a series of Bureau of Mines publications designed to serve the needs of Government and industry for comprehensive information on mineral commodities and activities. Copper, a versatile metal, has been vital to all civilizations from prehistoric times to the present. Its essential value in antiquity and until the nineteenth century arose from its malleability and ease of working, its corrosion resistance and durability', its attractive colors in alloyed and unalloyed forms, and, of course, its availability. The principal uses were for tools, utensils, vessels, weapons, pipe, statuary and other objects of art, and for building and architectural pur£~ses where formability, permanence, and beaut)" were necessary qualities. Utilization of copper based on these physical and mechanical properties has grown tremendously for commercial, structural, mechanical, architectural, and art items; and its capacity for forming numerous alloys has led to a myriad of applications from miniature copper and brass eyelets to huge bronze battleship propellers. The early nineteenth century marks the epoch of the greatest use of copper, transmitting electrical energy. This particular property of copper is fundamental to the spectacular growth of the electrical industry and all associated industries relying on electricity for power, light, and heat. More than half of all copper produced is used for transmission of electricity. The copper industry has been able to expand along with the mounting demand because of the ever increasing discovery of resources in the world and advances in mining, metallurgical, and fabricating technologies. World production and consumption rose progressively from about 18,000 tons in 1800 to more than 4.5 million tons in 1960. The estimated world reserve of primary- copper has more than doubled since 1935, being 212 million tons in 1960. Ninety percent of this reserve is credited to eight countries-the United States, Canada, Chile, Peru, the Soviet Union, Poland, Northern Rhodesia, and the Republic of the Congo. The United States share is 32.5 million tons of copper in ore, averaging approximately 0.9 percent. Another reserve being accumulated in the industrial countries of the world is copper products now in use that will eventually be discarded as scrap and become available for recovering secondary copper. In the United States this resource of more than 30 million tons, provides about one-fourth of the annual supply.

Jan 1, 1965

By Charles Vaught, Richard S. Fowkes, Ronald S. Conti, Barbara Fotta, William J. Wiehagen

The purpose of this study was to determine mine workers' state of fire-fighting preparedness and the technology being used to detect and respond to underground coal mine fires. To investigate this problem, 214 underground coal miners were interviewed by U.S. Bureau of Mines researchers. Frequency distributions of workers ' responses are presented in this report, along with segments of narrative accounts, to profile miners' fire-fighting capabilities. The data indicated that much variability exists from mine to mine and that there are several important changes operators may undertake in order to make miners better prepared to deal with fire underground: select appropriate sensors, establish and test a warning and communication protocol, construct a system capable of delivering hundreds of gallons of water per minute for sustained periods, institute formal fire preparedness audits, develop case studies of events that occur at an operation to use as teaching and assessment tools, and provide structured practice that can be incorporated into fire drills.

Jan 1, 1995

By Rick Wright, Gregory L. Raines

San Diego’s need to access underground space has dictated a long history of tunnel construction. The subsequent need for water, coupled with San Diego’s natural attractiveness, has led to significant population increases and the need for the construction of even more tunnels. This paper will provide a historical summary of the progression of mines, tunnels and trenchless technology construction projects that contributed to the advance of current technology, feasibility, and constructability. A bibliography of relevant reports and data is included.

Jan 1, 2001

By A. H. Harvey, M. Delangen, A. D. Fernie

"A large-scale expansion to Pacific Coast Bulk Terminals Ltd. has now been completed and placed in operation. The original plant, built approximately eight years ago, consists of the direct rail-car to ship transfer of bulk commodities. The extension includes additional rail-car unloading, a transfer house system for directing commodities to storage or ship, major storage and reclaim facilities, a second shiploader and a second deep-sea berth. In addition to the facilities for overseas shipments, a wood-chip loader and a barge berth have been installed for domestic shipments of wood chips and, occasionally, for other local commodities. The design considerations imposed by the nature of the products to be handled are covered in this paper."

Jan 1, 1969

By J. E. Chilton

Underground miners may be exposed to hazardous quantities of toxic gases, such as carbon monoxide (CO), generated from mine fires or explosions. Every underground miner is required to carry a filter self-rescuer (FSR), which when operated will remove CO from the miner's breathing air. In addition, every underground miner must have a self-contained self-rescuer (SCSR) near the worksite that will supply breathing oxygen. In many situations, miners do not know when to don either rescuer since they do not know if there is a fire in the mine, nor do they carry instrumentation necessary for the detection of the toxic, colorless, and odorless fire product CO. If each miner carried a personal CO alarm, which would respond to high concentrations of CO, the miner would then be alerted when to don either the FSR or SCSR and exit the mine. A prototype personal miner's CO alarm called PEMCOAL was developed by the U.S. Bureau of Mines. The PEMCOAL unit is small enough to be carried on a miner's belt, has a flash lamp visual alarm, requires no calibration for use, and uses a chemical sensor that changes color by reaction with trace quantities of CO. The chemical sensor was tested at concentrations of CO from 10 to 1,000 ppm, at temperatures from 5° to 40° C, and with several potential mine gas interferents. The PEMCOAL alarm times were sufficiently fast to warn miners before they are exposed to hazardous quantities of CO.

Jan 1, 1989

By James L. Ash

This report contains the results of a technical and economic evaluation of conceptual systems for the underground mining, rubblization, and in situ retorting of deep oil shale deposits. Study efforts were first directed towards evaluation of the applicable geology, associated minerals, rock mechanics, in situ retorting, access mining, ventilation, rubblization, safety, and environmental impact factors. Conceptual systems were synthesized and then evaluated against these factors from both a technical and limited economic viewpoint. The results of these evaluations were then analyzed and, based upon this analysis, the following two systems were selected for further study: System II: Room and Pillar-Vertical Drill and Blast System IV: Tunnel Boring-Horizontal Ring Drill and Blast Due to the large number of variables to be considered, a computer program was developed and utilized to provide data for the cost trade-off studies and economic analysis. Results of the early computer runs indicated the value of the tool available? in the computer program and led to an extension in the contract to determine the sensitivity of the systems to several of the more apparent significant variables. These results in turn led to a refinement in the design assumptions and a better understanding of the technical and economic options available to an owner-operator of a Vertical Modified In Situ Shale Oil Extraction System. This report is submitted in fulfillment of the requirements of Contract Number 50241073 by Fenix & Scisson, Inc. to the Denver Mining Research Center, United States Department of the Interior, Bureau of Mines. Work was completed as of November, 1976.

Jan 1, 1976

By L. S. Hansen

Organized efforts toward the prevention of injuries and occupational diseases have been of comparatively recent origin in the mining industry, dating generally from the beginning of this century. Mining-and particularly underground mining- is more hazardous in many respects than most other major industries, and continual and increasing attention has been given to its health and safety aspects. The importance of the physical well-being of those engaged in mining was recognized by Agricola, who, after describing the hazards encountered in 16th century mining operations, stated that "Some of these evils, as well as certain other things, are the reason why pits are occasionally abandoned." In the past 50 yr particularly, mine managements and labor organizations, separately or collectively, have mounted productive efforts toward the prevention of accidents and industry-associated diseases and illnesses. A statistical study of this period indicates that increasing awareness coupled with the endeavors of all concerned agencies has resulted in decreasing frequency of occurrences of injuries and illnesses. In recent years particularly the mining industry has used the services of safety engineers, industrial hygienists, inspectors, ventilation engineers and other specializing in locating and correcting deficiencies affecting the welfare of employees. Concurrently, the labor movement has incorporated into its organization individuals working in the fields of health and safety, many devoting full time to these responsibilities. Others serve in behalf of their fellow workmen as on-the-job safety representatives. Most authorities agree that accidents are caused by (1) unsafe acts, (2) unsafe conditions and, exceptionally, (3) Acts of God. The "unsafe act" often is cited as the prime cause. but many accidents, and attendant injuries, are the result of a blend of "unsafe acts" and "unsafe conditions," with each chargeable in varying proportions. It therefore is necessary to consider both the physical elements of the mine plant and the training, mental attributes and actions of all personnel involved. Analysis of an accident, if based on hasty reconnaissance and unduly hurried questioning, seldom will disclose more than surface causes and consequently will result in inadequate measures to prevent repetition. Mining involves unavoidable and calculated risks, as in all facets of life. It is most important then that men employed in mining be schooled in the hazards and develop fully the ability to evaluate and minimize risks. The environment, of underground mining often is harsh and strange compared to the more natural surface conditions man has learned to cope with as a part of established life patterns. The miner. therefore, must adapt to unusual situations and conditions and must develop a mental attitude permitting acceptance of change. 3.1-INDUSTRY-AFFILIATED SAFETY AGENCIES L. S. HANSEN There are many organizations primarily interested in health and safety. In addition to industry and labor groups, there are many private and governmental

Jan 1, 1973

By William R. Barton

Dimension stones, with their almost infinite variety, have a broad range of properties and uses. Natural stone was beyond doubt the first mineral commodity used by man. Today dimension stone has widened to encompass building exteriors and interiors, decorative and ornamental modes, statuary, monuments, paving, curbing, flagging, roofing, and miscellaneous categories such as blackboards, surface plates, and honestones. For many purposes, it competes with greater or less success with alternate materials such as concrete, metal, brick, plastic, or glass. The almost ubiquitous geographic distribution of stone resources is the basis for a dimension stone producer industry in almost every State and in almost every land. In the United States, alone, dimension stone sold or used by quarries is valued at 2 million to 3 million dollars annually. Mining, finishing, transportation, and use technology have been modernized, resulting in a broader spectrum of stone products and new adaptions in use. Increased efficiencies also have been reflected in costs and prices and, coupled with gains that should be realized from current research, auger well for continued vitality of the ancient and honorable dimension stone craft.

Jan 1, 1968

By Jr. Denton

This U.S. Bureau of Mines report presents the documentation for HEAPREC, a methodology for calculating reclamation performance bonds for cyanide heap leach operations. HEAPREC is a template developed for use with Lotus 1-2-33 release 2.01 or newer software. The report is presented in step-by-step "user's manual" format. Appendices contain detailed background and reference material on performance bonding, cyanide detoxification regulation, cyanide detoxification methods, general mine reclamation procedures, and an example bond calculation.

Jan 1, 1992

By Charles Vaught

The purpose of this study was to determine mine workers' state of fie-fighting preparedness and the technology being used to detect and respond to underground coal mine fires. To investigate this problem, 214 underground coal miners were interviewed by U.S. Bureau of Mines researchers. Frequency distributions of workers' responses are presented in this report, along with segments of narrative accounts, to profile miners' fire-fighting capabilities. The data indicated that much variability exists from mine to mine and that there are several important changes operators may undertake in order to make miners better prepared to deal with fire underground: select appropriate sensors, establish and test a warning and communication protocol, construct a system capable of delivering hundreds of gallons of water per minute for sustained periods, institute formal fire preparedness audits, develop case studies of events that occur at an operation to use as teaching and assessment tools, and provide structured practice that can be incorporated into fire drills.

Jan 1, 2010

By Yiming Sun, John Stolz, Jakob Walter, Drew Mason

The Courthouse Commons SEM Tunnel was excavated within 6 feet of cover beneath two buildings in downtown San Diego utilizing high-precision geotechnical instrumentation. The excavated dimensions are approximately 25 feet in diameter and 328 feet in length connecting two in-service detentionlevel security buildings. Presupport includes large-diameter grouted canopy pipes and smaller pipe spiles. Initial support consists of fiber-reinforced shotcrete with lattice girders. This paper presents observed ground and structure behavior and lessons learned. During construction an unanticipated brick structure was encountered, and methods were developed to improve adhesion of shotcrete to sandy soil and to reduce rebound

Dec 1, 2022

These inspection standards have been prepared for use in the Federal inspection of bituminous and lignite mines. They are a revision of "Tentative Coal-Mine Inspection Standards," published as Bureau of Mines Information Circular 7204 in February 1942 and employed a guide for Federal inspections. Numerous changes have been made in the original standards owing in part to recognition of shortages of some types of safety equipment due to the war, in part because of need of additional standards to cover certain mine conditions' arid' practices, and in part to conditions not foreseen when the original standards were prepared. About one-fourth of these standards are marked with an asterisk (*) as being of particular importance in preventing accidents in many coal mines; however; failure to carry out the suggestions made in such of the other standards as are applicable may also' lead' to the loss of lives.

Jan 1, 1943

By James R. Evans

Orange County, adjacent to the populous and industrialized Los Angeles area, is the fastest growing county in California and is second only to Los Angeles County in total population (figure 1). In addition to an equable climate and a burgeoning economy, there is room in Orange County for growth and expansion. Growth over the past decade has resulted in rapid development of industrial tracts, housing areas, and shopping and commercial centers, mostly in former agricultural areas. The value of new building in 1972 was a record amount-over I billion dollars (figure 2). Problems relating to the proper direction of growth are the concern of both government and the private sector. The intelligent and efficient use of areas to be developed requires planning for the conservation and protection of the County's natural beauty and for the orderly development of natural resources. The availability of sand and gravel, which is used in many phases of construction, will be a major controlling factor in the future of the County.

Jan 1, 1974

By C. J. Bise, M. F. Sindelar

Regulations, such as the MINER Act of 2006, require the installation of redundant and secondary communication systems to assure that contact can be established with coal miners who may become trapped underground as a result of an event such as a fire, explosion or inundation. For half a century, the orientation towards underground communications has been that more complex systems better serve the coal miner. However, if a goal is to provide for an alternative means of establishing communication between the surface and trapped miners underground, then some of the technology employed should be simple, reliable and cost-effective. Coal mines spend hundreds of thousands of dollars on exploratory drillholes to characterize reserves, sometimes decades ahead of mine development. During the pre-mine planning phases, certain exploratory drillholes could be located and then outfitted with a simple communication link that would remain compatible with the continuing evolution of communication systems. Inexpensive links, whose locations would be accurately recorded, would be exposed by continuous miners during mine entry development, thereby allowing an underground phone to be connected to a surface station in the event of an emergency. A latent network of these communication links could be installed for less than $500 each, minimally affecting drilling and grouting operations, and could be designed to be compatible with many communication devices. This research examines methods and materials for incorporating an embedded communication link during pre-mine exploration drilling, addresses significant factors affecting its implementation, and presents a recommended design. Since mine plans are known to change, the objective is to minimize cost so that, if not used, the investment is minimal for a potential secondary means of communication between the surface and underground workings.

Jan 1, 2014

By D. J. Parker, D. Harrington, L. H. Harrison

"INTRODUCTION The necessity for protection against the hazards of lightning manifests itself from time to time in the mining industry by reason of loss of life, damage to electrical equipment, fires in surface structures at mines, and accidents in the handling and use of explosives. This paper is intended to assemble, correlate, and present some of the salient points embodied in the available literature on the subject and at the same time give some factual data concerning instances of such loss of life and damage to property, with special application to the mining industry.The annual loss of life and destruction of property by lightning is considerable; the former may be prevented to a limited extent, though use of common sense as to exposure is required and not always followed; the latter can be prevented to a considerable degree. The manufacturers of electrical equipment, through improved types of lightning arresters, have done much toward the protection of electrical equipment, with consequent safeguarding of life and of property. Education based on unfortunate experiences has gone far to discourage the handling of explosives and blasting accessories during thunder storms, especially in open pits and quarries, and to a much smaller extent in underground workings. The lowly lightning rod plays an important role in the protection of certain types of buildings (especially isolated buildings), stacks, monuments, and other structures.LIGHTNING PHENOMENAIn 1751, Franklin proved that, lightning was simply a visible display of electricity - an extended spark; and until a generation ago little had been added to his exposition to define the various phases of the phenomenon. Matters pertaining to lightning are discussed in the following references:"

Apr 1, 1948

By John B. Goodman

This report summarizes the work done by the Koppers Company, Incorporated, in cooperation with the Bureau of Mines on the commercial evaluation of the primary low-temperature tars produced from Texas lignite in the Rockdale, Tex., plant of the Aluminum Company of America in conjunction with the Texas Power and Light Company. The interest of the Bureau of Mines in this project is twofold. First, through its cooperative agreement with the Texas Power and Light Company the Bureau has assisted in the technical design and practical operation of the prototype, externally heated, entrained-state carbonizer for producing char for electric-power production and for primary low-temperature tar. Second, the first successful operation of the prototype carbonizers employing the Bureau of Mines-Parry process on lignitic coal in 1953-54 led to the production of large quantities of primary lignitic tar, concerning which too little was known or had heretofore been published in this country.

Jan 1, 1959

By P. H. Francis

In This report, factors which currently enter into the design, manufacture, and quality assurance of explosion-proof enclosures are reviewed, with special emphasis given to the sealing concepts and sealants/cements, per se, for lenses. The physical and mechanical properties of a number of representative sealants and adhesives are measured, and found to exhibit great variance, with few discernible trends which might afford a firm base on which to establish minimum property standards. Accordingly, acceptance criteria for adhesives and sealants are suggested based on the survivability of an explosion-proof enclosure as a structure rather than upon the minimum mat real properties of its constituents. Procedures or surface preparation of adherends, and for quality assurance, also are proposed.

Jan 1, 1980

"Guideline Augered Cast-In-Place (ACIP) Pile Specification and Commentary11.0 GENERAL1.1 SCOPEThe Pile Contractor shall furnish all labor, materials, tools and equipment necessary for furnishing, installing and testing Augered Cast-in-Place (ACIP) piles as shown on the Contract Drawings and as specified herein.ACIP piles are commonly referred to by several other names. Some of them are trademarks or service marks owned by Foundation Contractors and some are names that try to describe the installation process. The term “cast-inplace” is sometimes replaced with “cast-in-situ,” especially in Europe. Some common names are Auger Cast Piles, Intruded Mortar Piles, Augerpress Piles, Augered Pressure Grouted Piles, AugerPile Foundations, Continuous Flight Auger (CFA) Piles, Grouted Bored Piles, Augered Grout-Injected Piles, Drilled or Augered Uncased Piles, and Uncased Cast-in-Place Concrete Piles. To avoid confusion, ACIP pile will be used exclusively herein.1.2 PILE CONTRACTOR QUALIFICATIONSThe ACIP piles shall be installed by an experienced Pile Contractor who upon request of the Engineer shall submit evidence of successful ACIP pile installation under similar job and subsurface conditions, including a job supervisor who shall have a minimum of five years of method specific experience.The proper installation of the ACIP piles is dependent upon the procedures used by the Pile Contractor’s field representatives and equipment provided. The Pile Contractor’s personnel responsible for the installation should have relevant experience with the auguring and pumping equipment, experience placing piles under similar site conditions (including restricted headroom if appropriate), in similar subsurface conditions, as well as experience handling the special grout mixes, admixtures, etc."

Jan 1, 2016

By E. V. Cilento, R. C. Laotz, K. A. DiGregorio

"PULMONARY ALVEOLAR macrophages (PAM) protect the lungs by providing a first line of defense against inhaled foreign debris and bacteria. In this role PAM phagocytize foreign matter, secrete enzymes that augment microbial killing and digestion, and produce reactive oxygen me-tabolites (2, 3, 18, 19, 22, 26). However, in addition to this antibacterial function, PAM participate in a diversity of functions, such as tissue repair, lipoprotein metabolism, and immunoregulatory activities (11, 22).Studies have suggested the existence of a heterogeneous population of PAM with respect to immunologic function, enzyme release, phagocytosis, morphological characteristics, expression of membrane receptors, ad-herence, and superoxide (O2•) release (4-7, 10, 16, 21, 23, 28). This heterogeneity has been observed by analyz¬ing subfractions of PAM separated by cell density frac-tionation. For example, using guinea pig PAM, Dauber et al. (7) showed heterogeneity in cell density and size, morphological characteristics, and cytochemical properties, whereas Holian and co-workers (16) reported variations in migration, chemotaxis, O2• release, and pinocytosis among subfractions collected. Similarly, O'Neill et al. (21) observed functional heterogeneity in rat PAM with regard to phagocytosis, O2 • release, and lysosomal enzyme activity.Several investigations have reported a correlation between PAM activity and cell volume. Most studies have shown that O2 release from PAM increased with decreasing cell size (15, 21, 25), although Bielefeldt Ohmann and Babiuk (4) reported a decreasing trend. However, Gallin (13) has suggested that significant variability may even exist within density-defined or cell-volume subfractions that could lead to misinterpretation of results concerning PAM heterogeneity.A better understanding of the heterogeneity in O2 production may be obtained by using single cell meas-urements to evaluate whether functionally distinct sub-populations actually do exist. As such, the present study was designed to examine heterogeneity in O2 • release from single PAM using a recently developed electrooptical technique (8). The initial oxygen metabolite, O2•, produced by NADPH oxidase at the surface of the plasma membrane, was measured by quantifying the reduction of nitro blue tetrazolium (NBT I to a diformazan precipitate. Measurements were made from video recordings of individual cells stimulated by their adherence to the bottom of a culture dish. The cell volume and degree of spreading also were determined directly from the same video recordings, and the data were correlated with the initial rate and maximum amount of diformazan produced by the same cell."

Mar 1, 1992

By Oliver Bowles

ASBESTOS is a name applied to a group of naturally fibrous minerals. As indicated in a later section devoted to a detailed discussion of the early history of asbestos, the tern may be defined as a. fibrous form of serpentine or amphibole. It does not include fibrous forms of other minerals, such as wollastonite, nemalite (fibrous brucite), or the fibrous forms of calcite or gypsum. A material that has the characteristics of silk or cotton and at the same time will not burn is unique. Because it combines these qualities with other advantageous properties, asbestos has specialized uses for which no substitutes are yet available. Asbestos furnishes a major raw material for a great variety of essential products and their manufacture constitutes a vast industry. The United States leads all countries in the manufacture of asbestos products. The value of such commodities manufactured in 1952 exceeded $332 million. They are not only of vast importance to budding construction and industry but axe absolutely, essential to certain important fields of use, for example, steam packings and friction materials, such as brake-band linings on automobiles.

Jan 1, 1955