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By Askari-Nasab, D. Checkel, K. Awuah-Offei

Life Cycle Assessment (LCA) is an emerging environmental management tool for examining environmental impacts from cradle to grave. In this paper, LCA is used to evaluate the acidification potential (AP) and global warming potential (GWP) of belt conveyors and truck haulage systems in a surface gold mine using the ISO 14040 standards. The results show that, for AP, the truck system has 32 kg of equivalent SO2 per functional unit, compared to 8 kg for the conveyor system. However, for GWP, the conveyor has 2,820 kg of equivalent CO2 per functional unit, compared to 648 kg for the truck option.

Jan 1, 2009

By John C. Machisak

STATISTICAL data on injuries and employment pertinent to metal mines and to their mills, and/or processing plants are presented in this Information Circular for the calendar year 1960. The information pertains to metal mines, as well as ore-dressing plants and primary nonferrous smelters, refineries and reduction plants, and their auxiliary works. These data are voluntarily submitted annually to the Bureau of Mines by the operators, and contribute greatly toward the promotion of safety in the mineral industries. The data presented are classified according to the principal mineral produced and include information on copper, iron, lead-zinc, gold-silver lode, gold placer, uranium-vanadium and miscellaneous metals. A breakdown of miscellaneous metals by commodities is shown in table 19, page 41. The data also relate to workers engaged in production, exploration, development, construction, and maintenance and repair work, as well as supervisory personnel and office- workers at the mine or plant site. Injury and employment data at metal mines and metallurgical plants in the United States for 1960 are shown under the following general sections:

Jan 1, 1963

By Vincent Tirolo

The proposed Second Avenue Subway is a new two-track subway line running from 125th Street and Park Avenue at the north, east along 125th Street to Second Avenue and south along Second Avenue to the Financial District in lower Manhattan, NY with 16 new stations and 13.6 km (8.5 miles) of track. The project has been broken into four construction phases. The initial Phase 1 operating segment includes three new stations (96th, 86th and 72nd Street stations) with a connection to the existing Broadway line at the 63rd Street Station at Lexington Avenue. Rehabilitation of the 63rd Street Station is also included in the scope of Phase 1. Subsequent phases extend service north and west to 125th Street (Phase 2), south to Houston Street (Phase 3) and finally to Hanover Square (Phase 4). The DMJM Harris/Arup Joint Venture (DHAJV) prepared the Contract Documents MTA for Phase 1. Parsons Brinckerhoff is providing the MTA with construction inspection services for Contract C-26002. In April 2007, NYCT awarded first Phase 1 for $337 million to S3 Tunnel Constructors, a tri-venture comprised of Skanska USA Civil, Schiavone and Shea. Contract C26002 is for the construction of the tunnel boring ma-chine (TBM) launch box and the mining of the TBM tunnels from 92nd Street to 63rd Street. The major part of the contract is to construct a shaft, commonly referred to as the launch box, from East 92nd Street to East 95th Street having dimensions of 244-m- (800-ft-) long by 18.9-m- (62-ft-) wide and a depth of 19.8 m (65 ft), including more than 91,000 m3 (119,000 cu yd) of soil and rock contained within its walls. The launch box will ultimately become the southern half of the 96th Street Station. The focus here is geological conditions at the launch box and existing structures along the launch box. These geologic conditions and existing structures had a major influence on the selection and design of the support of excavation system (SOE), the SOE bracing system, construction staging, the ground movements, dewatering and other challenges of constructing the launch box (Fig. 1).

Jan 1, 2013

Severe whipping of shuttle car trailing cables occurs when the car stops suddenly or reverses direction. This causes cable damage, and can seriously injure personnel near the cable. FMC has contracted with the U.S. Bureau of Mines to design, build and demonstrate a reel control system that will significantly reduce or eliminate whipping. II. CONCLUSIONS Results of engineering effort show that the following conditions are primarily responsible for the whipping problem. Causes may exist individually, or in combination.

Jan 1, 1972

By Sandy Worden

Coal mining companies in Australia are managing the high-consequence risks across their operations more effectively by using an interactive online risk management system known as Riskgate Developed by the Minerals Industry Safety and Health Centre (MISHC) at the University of Queensland, Australia, Riskgate contains detailed information about 11 high-consequence risk areas (called topics in the system) for opencut and underground coal mines (Table 1). The existing topics are: fires; strata control for underground mining; ground control for opencut mining; tires; isolation; collisions; explosions and explosives; manual tasks; and trips, slips and falls. Every Riskgate topic is focused on coal industry activities (mining, processing, transport and storage). The scope includes mine sites, lease areas and mine infrastructure (mobile, fixed plant, field equipment, buildings, road and rail transport), and all aspects of the mine life cycle from design through to decommissioning. The topics uniformly recognize that a loss of control can result in injury or fatality, equipment damage, production loss, reputation loss and environmental damage. However, the priority focus for Riskgate is the safety of mine personnel.

Jul 1, 2013

By F. De Lucio

Para la aplicación de la instalación de un sistema de relleno hidráulico es necesario evaluar las funciones que el relleno debe contener y determinar si el material a usar cumpla con las funciones especificadas. En ese sentido, el objetivo del texto presenta una interpretación científica sobre tal método para especificar las funciones que el relleno deba cumplir y la metodología experimental adecuada que evalúe cuantitativamente a un relleno hidráulico.. Asimismo, se describen sus propiedades estructurales como la densidad relativa, reducción de volumen y estabilidad de tajeos contínuos, así como los métodos indirectos para inferir dichas propiedades y las posibles consecuencias secundarias que pueda generar el empleo de relleno hidráulico.

Nov 20, 1972

By R. Stefanko

In this report, the use of Penn State Ventilation Simulator (PSU/MVS) for planning and evaluating new coal mine ventilation systems is demonstrated. The simulator's application to evaluate the ventilation system of a coal mine currently under development is discussed. The ventilation system is evaluated for representing development of the mine at the end of 12, 24 and 36 months after mining has begun. The report describes the necessary steps of data input preparation, ventilation network development, analysis of results, modifications to the network, and methods to expand the computer program for networks larger than 550 branches.

Jan 1, 1977

By William F. Hahn

This report describes an illumination system suitable for use in a slope under construction, Simulator work was performed using actual lighting hardware to verify adequate light levels to meet MSHA proposed regulation (as published in the Federal Register, January 13, 1977). The sequence of operating activities for two different slope driving sites are discussed and lighting requirements are defined for each,

Jan 1, 1981

Research personnel from the Bureau of Mines, a representative of the Mine Safety and Health Administration, and research contractors for the Bureau of Mines met with other Government and industry representatives at three seminar locations in December 1980 to discuss the findings and products of Bureau research on mine safety training. The research program is aimed at providing assistance to the mining community in its efforts to reduce industrial-type, human-error accidents through research establishing performance based methods and media for employee training. Research emphasis is directed toward development of baseline materials and instructional models; development of methods for structuring and evaluating health and safety, supervisory, and occupational training; and the continued investigation and application of current learning and simulation technology that could significantly enhance the effectiveness of training opportunities.

Jan 1, 1981

By W. H. Somerton

Many oil-producing formations contain significant amounts of clay. Because of the large surface area and reactivity of such surfaces, the response of the formations to various recovery processes may be dominated by the reactions of fine-grained minerals, including clay minerals, in the formations. Thus, the success or failure of enhanced oil recovery (EOR) methods may be controlled to a large extent by the amount and nature of these minerals in the formations to which the methods are being applied. One of the deterrents to the successful application of chemical EOR methods is the loss of chemicals injected into the formation, to non-oil recovery processes. These chemical loss processes include adsorption onto mineral surfaces, chemical reactions with rock and fluids in the formations, possibly leading to precipitation and plugging of the formation, and trapping of chemicals in parts of the rock structure so that they become unavailable for displacing oil. Chemicals that may be injected include surfactants, polymers and caustic solutions which react with organic acids in the crude oil to produce surfactants in-situ. These losses are most pronounced in fine-grained reservoir rocks containing substantial amounts of clays.

Jan 1, 1984

By Joel N. Van Sant

THIS REPORT describes the occurrence, mining, and use of refractory clay in Colorado within Region III of the Federal Bureau of Mines, which includes the States of North arid South Dakota, Nebraska, Wyoming, Colorado, Utah, New Mexico, and Arizona. Field work by the Bureau of Mines, United States Department of the Interior, included examination of active and abandoned refractory-clay mines as well as a reconnaissance survey and sampling of numerous clay-bearing formations exposed in Colorado. Information from the survey and the sampling will help guide private industry in its search for virgin sources of refractory clay. Library research of published and unpublished reports from various Federal, State, and private sources was conducted during the early phase of the investigation. Most of the refractory clay mined in the Denver-Golden district of Colorado is not used for refractory purposes but is blended with other clays in the manufacture of structural clay products. The predominantly flint-clay de-posits in the Pueblo and Fremont County districts are mined and utilized chiefly in fabricating refractory products.

Jan 1, 1959

By Ralph B. Stevens

The objective of this 20-month program was to define the relationships between mine ventilation, temperature, humidity, ore properties, material's used in mine operations, etc., and the spontaneous combustion problem in underground metal mines. Tradeoff studies of availability, reliability, cost, and maintenance of spontaneous combustion protection sensors and telemetry were conducted, after which a prototype system was selected from four design alternatives. This selected system was then laboratory tested and demonstrated in an underground copper mine.

Jan 1, 1979

By Harmon E. Keyes

Many organizations, including the Bureau of Mines, have made intensive studies of the application of leaching methods to relatively small low-grade disseminated deposits of copper ores, containing both oxide and sulphide minerals. One of the principal difficulties has been to obtain a solvent that could be made at a low cost and would effectively dissolve the copper minerals. Another drawback has been the high initial cost of a plant and the refined type of mechanism ordinarily required by standard practice for carrying out the leaching cycle. The Bureau of Mines has attempted to develop a cheap and efficient solvent that would especially meet the requirements of smaller plants. (See Bibliography.) It has been known that dilute ferric sulphate-sulphuric acid solution is an excellent solvent for most copper minerals, such as chalcocite, bornite, and oxidized forms, but not for chalcopyrite and certain silicates. A method of producing this solution from sulphurous products and waste liquors was developed by the bureau and tried successfully on a test-plant scale at the Southwest Experiment Station in cooperation with the department of mining and metallurgy, University of Arizona, Tucson, Ariz. However, this work did not involve the actual leaching of ores with the solutions thus produced or the cyclic use of the iron solutions in the regenerator cell. Except for certain laboratory tests, in which known impurities were added, no data were available to show the effect on regeneration if accumulations of impurities were built up in the leaching circuit.

Jan 1, 1930

By John P. Capp

After World War II the Bureau of Mines studied methods of producing synthesis gas including a plan to gasify coal in place. Consequently, under a cooperative agreement with the Alabama Power Co., Bureau engineers directed a series of experiments that were carried out on the property of the Alabama Power Co. at Gorgas, Ala. The purpose of underground gasification of coal, regardless of method used, is to obtain the energy contained in the fuel for use on the surface, without mining in the usual sense of the term. Underground gasification can be described as (1) a process where coal, in place, is consumed by partial combustion with air, oxygen, steam, or any combination of these to produce a low calorific value gas (80 to 300 Btu per cu ft) or (2) a complete combustion process in which air is used to produce a gas containing carbon dioxide, nitrogen, and considerable thermal energy.

Jan 1, 1963

By Donald E. Redmon

This Bureau of Mines report reviews injury experience in the metallic mineral industries for 1966-67. For each of the years, 27 tables summarize disabling work injuries by department, source of injury, extent of disability, part of body injured, and nature of injury. Correlative information on employment, worktime, and operating activity is also presented.

Jan 1, 1973

By Forrest T. Moyer

All general measures of the safety record of the coal mining industry worsened appreciably in 1970. Injury experience for the year was 260 fatal and 11,552 nonfatal injuries at respective frequency rates of 1.00 and 44.40 per million man-hours of worktime. The fatality total was 57 higher and the rate of occurrence was 18 percent higher than the corresponding figures of 203 fatal injuries with a frequency rate of 0.85 in 1969. The worsened fatality record in 1970 resulted primarily from a major disaster (a single accident which results in the death of five men or more) on December 30, 1970, that killed 38 men. There were no major disasters in 1969. The total of 11,552 nonfatal injuries in 1970 was the highest annual total since 1960. It was 1,635 higher and the frequency rate was 6 percent higher than the corresponding totals for 1969 of 9,917 nonfatal injuries occurring at a rate of 41.76. The injury severity rate of 8,308 days lost or charged per million man-hours was 13 percent worse than that of 7,359 in 1969. Similarly, the average severity of 183 days lost or charged per injury in 1970 was 10 days or 6 percent higher than in 1969. Aggregate worktime of 260.2 million man-hours and production of 609.8 million tons in 1970 were, respectively, 10 and 7 percent higher than in 1969. An average of 144,480 men were at work on an average of 227 active days in 6,316 mines and 544 mechanical cleaning plants during 1970.

Jan 1, 1973

By F. A. Rutledge

[An a part of the United States Department of the interior program for the development and use of Alaska raw materials, the Bureau of Mines is conducting an investigation of deposits of nonmetallic minerals accessible to the Alaska Railroad for use in building; materials is In the Alaska Railroad-belt area. The results of the investigations, to date, indices that raw materials for the preduction of brick products are in plentiful supply as cloy in the Anchorage area, as fire clay at Sheep Mountain, and as shale in the Healy Creek coal formations near Healy, Alaska.]

Jan 1, 1953

By D. T. Randall

The burning of coal without smoke is a problem that concerns the Government directly because of the advantages of smokeless combustion both in public buildings and on naval vessels. In addition, smoke abatement is a factor in conserving the fuel resources of the United States. Hence, as part of its general investigation of the best methods of utilizing the coals of this country, the Bureau of Mines, which is in charge of the fuel-testing work formerly carried on by the United States Geological Survey, has made extended tests to determine the conditions necessary for the smokeless combustion of bituminous coal in boiler furnaces. Bulletin 39,¢ a preliminary report, treats the smoke problem from a theoretical point of view, detailing the steps that are being taken by municipalities, manufacturers, and citizens to abate smoke, also showing the possibility of a clean city. The present bulletin not only shows that bituminous coals high in volatile matter can be burned without smoke, but also that large plants carrying loads that fluctuate widely, where boilers over banked fires must be put into service quickly and fires forced to the capacity of their units, can be operated without producing smoke that is objectionable. Proper equipment, efficient labor, and intelligent supervision are the necessary factors.

Jan 1, 1918

By Thomas G. Chapman

The four major steps in the production of marketable copper are mining, concentrating, smelting, and refining. In a few cases, however, leaching takes the place of concentrating, smelting, and refining, and in others ores are smelted without being concentrated. Copper ores have been milled since the early days of mining in the United States. Except in the Michigan district, most copper ores went direct to the smelter until the so-called porphyry mines were developed. At present, although considerable leaching and direct-smelting ores are produced, the bulk of the copper ore mined is concentrated. Improved methods of concentration have kept pace with the increased tonnages of ores milled.

Jan 1, 1936

Minerals are vital to any industrialized civilization. Annually, the United States uses more than 4 billion tons of new mineral materials, or about 40,000 pounds per person-about half being mineral fuels and the other half metals and nonmetallics. Stable and economic domestic mining, mineral, metal, and mineral reclamation industries are essential to the economy. The value of United States energy and processed materials of mineral origin exceeds $200 billion annually. Although a number of minerals are imported, especially some designated as "strategic and critical," most U.S. mineral supplies are derived from the domestic mines and processing facilities that you will be seeing, reading about, and visiting as you use this visitor guide. We hope you enjoy your experiences. This pamphlet, a guide to mining and mineral operations that may be observed or visited and some other points of interest relating to minerals, is intended to aid tourists and students who are interested in mining. Some may wish to study our Nation's romantic past; others may plan to enter the minerals industry as a career; still others may have a primary interest in conservation practices. The pamphlet is also intended to aid State and local officials, Chambers of Commerce, and mining firms in answering some of the many questions of tourists and students.

Jan 1, 1977