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By Oswaldo Carhuancho

El presente trabajo señala la filosofía de trabajo en equipo desarrollada en la mina Pierina, Lima. La política de trabajo se sustenta en el pensamiento de Barrick, donde las prácticas administrativas basadas en la seguridad, salud ocupacional y el medio ambiente repercuten en el beneficio de sus empleados, accionistas y las comunidades en las que opera. Por ello, la primera preocupación de la empresa debe ser el trabajador y no las máquinas, así como la labor de los jefes no se limita a una actitud paternalista, sino a una democrática, de forma que el empleado asume sus responsablidades con seguridad y eficiencia. Como consecuencia de ello, se redujeron la cantidad de hombres-accidentess, se elevó el costo de producción y se redujo, la cantidad de personas en la supervisión de operaciones mina.

Sep 13, 2001

By K. E. Yassin, A. Yehia, M. Amar

Phosphate fines (size ≤ 45 μm), from the Red Sea Region, Egypt, were subjected to beneficiation process to recover the phosphorite grains from such fines. The sample is characterized by low P2O5 content (18.78%) associated with gangue minerals such as silica (22.77% SiO2) and carbonate (2.01% MgO) indicating its low grade. Phosphate pre-concentrate was prepared by gravity separation, using Falcon, where 63.37% of the phosphate, with 24.94% P2O5, 1.46% MgO, and 10.54% SiO2, was firstly recovered reducing the mass flow to the subsequent beneficiation process. However, the gravity tailing was the feed for the reverse phosphate flotation using bench scale column flotation where oleic acid was used as a carbonate gangue collector and amylase enzyme as a phosphate depressant. Under the appropriate flotation conditions (0.1% amylase, 5·10−4 mol/dm3 oleic acid, and temp. 30 °C), phospho-concentrate assaying 0.61% MgO, 13.14% SiO2, and 27.85% P2O5 with a P2O5 recovery of 55.45%, was finally obtained without the use of expensive depressants, e.g., phosphoric acid or sodium silicate. A tentative flow sheet for the whole process was postulated.

By Louise H. Michaud

Albian Sands Energy is scheduled to begin production at its oilsands operations in the fall of 2002. Start-up includes the selection and implementation of over 75 IT systems or computer applications. These include engineering applications, systems required to control mining activities, maintenance, the processing plant and utilities, and also systems required to run the company, such as human resources, finances and inventory/warehousing. This paper outlines the processes used for the selection, implementation and integration of these systems in order to optimize the use of information and to meet the technical, business and IT requirements of the company. The first step in Albian?s approach to identifying system requirements is the development of a Business Activity Model, outlining all tasks involved in running the operations. The computer applications required to accomplish each task are then identified by having the IT team work closely with each technical and business unit. Historically, at some companies, the selection of systems has been lead by the IT team or by consultants, with little input from the technical or business units. Typically, this results in products that don?t meet the company?s expectations. To ensure a more positive outcome, Albian believes that it is imperative that the company?s technical and business people are closely involved in the selection process. Integration of the IT systems is also key, including linking all applications through a Data Warehouse and EDMS. Over 120 required integrations have been identified. This ensures the storage of all data in only one location, data security, and easy data and document retrieval for all requirements throughout the company.

May 1, 2002

Coal-bearing regions cover about 18,464 square miles or one third of Iowa, primarily in the south-central part of the state. Coal quality ranges from subbituminous to high volatile bituminous. Iowa's coal reserves are estimated to be 2.2 billion tons, less than one-half of one percent of total U.S. reserves. Coal beds are typically thin seams with a maximum thickness of five feet. Coal deposits in Iowa were fist mined in the 1840s for blacksmithing and domestic purposes. Demand for coal increased with the use of coal to fuel steamboats and railroads. Production peaked in 1917, when Iowaproduced9 million tons of coal. Since then, conversion to natural gas and fuel oil has decreased the demand for coal. Today, electrical power generating plants have created a continuing, but declining, demand for Iowa's coal. Coal production in Iowa is by surface mining methods. The Iowa regulatory program was conditionally approved January 21, 1981. Full approval was received March 28,1982, and the Abandoned Mine Land Program was approved March 28, 1983.

Jan 1, 1992

By J. F. McIlwain

Cobalt-base hardfacing alloys used for wear resistance consist almost entirely of metals largely imported into the United States. As part of an overall research program to help alleviate this foreign dependency, the Bureau of Mines has been investigating an iron-base alloy system as a potential replacement for cobalt-base alloys for some uses. To ascertain the melting ranges, thermal analyses were made of cast heats of alloys containing, in weight percent, 59-61 Fe, 16-19 Cr, 8-9 Ni, 1 Mn, 1 W, 1 Mo, 0.5 Cb, 0.6 Si, 0.3 C, and 0-12 stoichiometric TiB2. Powder alloys within this range of composition, prepared by mechanical alloying, were sized and applied to mild steel test coupons by nontrans-ferred-arc plasma spraying. The resulting thin coatings were >95 pet dense, with bond strengths of 35 MPa and hardness of 400 to 840 DPH. Abrasive and adhesive wear test data were compared to those of a plasma-sprayed cobalt-base alloy. A range of boride contents resulting in most promising properties was determined for further research.

Jan 1, 1985

"THE CONCEPT of energy as a commodity, while not entirely new, is not as widespread as the importance of the idea to this modern world would lead one to expect. The growth in the supply and use of energy over the past years has been tremendous, but our very closeness and familiarity have somewhat distorted the viewpoint, particularly of the younger generation. To many of us who remember the wonderful satisfaction of our first responsibility for directing two horsepower hitched to a farm cart or hay wagon, there still arises a feeling of some awe at the casual flick of the switch with which our sons and daughters summon to their convenience the service of some one hundred or more horsepower.Energy is the vital component of our existence and, no matter what contempt our day-to-day familiarity may •breed, it is wise to .pause from time to time and consider our national energy standing. Have we still capital in the bank? Are our expenditures wisely •conceived and well directed? Is provision being made for the years •ahead for the needs of our children and our children's children?"

Jan 1, 1953

Case studies from four western states are used to illustrate the impact of the environmental compliance process on the mining industry. The case studies were not chosen as a statistically significant sample of all mining operations in the western United States but were chosen as representative of operations on both public and private lands and in locations that exhibited varying degrees of involvement by governmental units, non-governmental organizations and the general public. Basically, each case study was chosen because some aspect of their environmental compliance process helped to illustrate an interesting point in the regulatory process. The criteria used to select the case studies were: mines located in different jurisdictional areas, mines located in varying geological areas~ mines located in areas having different historical relationships with mining: and operations that are in production as well as those seeking an operating permit. The variety of such projects should provide the necessary foundation to evaluate the impacts of the environmental compliance process in each location.

Jan 1, 1994

By S K. Das

An intensive investigation into modern roof support technology, including hy draulic and control systems, has been carried out against the perspective of global development and support behaviour on longwall faces across the Indian sub-continent. The wide ranging study examined various types and designs of modern supports used in seams of varying thickness and inclination where caving and stowing were practised. Consideration has been given to structural analysis, support resistance, the various forces acting over and on the powered supports and to support compatibility. The examination of the phy sical parameters has been allied to field experience and, together, have led to the formulation of standard designs for both the powered support structure and structural systems. A realistic mathematical model has been formulated for calculating the capacity of roof support requirements resulting from the actual behaviour of the immediate roof stratum. As a result of the work, it should be possible to readily select the most appropriate type of support sy stem for the conditions and longwall mining method that is to be employed.

Jan 4, 1997

By R. D. Lawrence

Suggestions have been made that the appraisal of mining assets using discounted cash flow techniques should be based solely on proven and probable reserves in reliance upon the widespread international recognition of uniform resource definitions. Following a review of general accepted valuation principles, a survey of the literature and, most importantly, a review of real transactions in the open market, it is clear that valuators should not be constrained by the growing acceptance of modern mineral resource codes. On the contrary, valuation practitioners should be encouraged to examine all classes of mineralization and, after making due allowance for risk, to utilize all mineral resources as a basis for determining fair market value.

Jan 1, 2000

By S. Saluja

El presente texto describe las aplicaciones de los pernos de roca como un sistema de sostenimiento en la minería. Asimismo, se comparan los distintos tipos de pernos de roca, se muestran los pernos de roca de madera y la función de los tijerales de sostenimiento en la prevención de la comba del techo.

May 1, 1981

By Richard M. Winar

In September of 1988, the United States Environmental Protection Agency (US EPA) published final regulations that effect owners and operators of underground storage tanks (USTs). These regulation include stringent technical requirements for owners and operators of USTs containing petroleum and certain hazardous substances. The technical requirements effect both new (those installed after December 1988) and existing USTs and include notification; performance and operating standards; release detection, reporting, investigation; release response and corrective action; and closure requirements for out-of-service USTs. The USEPA also published final regulations regarding financial responsibility requirements for owners or operators of petroleum USTs in October of 1988. These regulations require owners or operators of petroleum USTs to demonstrate financial responsibility for the costs of corrective action and compensating third parties for bodily injury or property damage caused by releases from petroleum USTs. Like thousands of other industries, the mining industry must become thoroughly familiar with these new regulations in order to properly manage their UST systems, ensure compliance, and understand other ramifications imposed by these regulations.

Jan 1, 1990

By G. Watson, S. Sawyer

A Method to Calculate Hydrodynamic Loads on Underground Bulkheads Bulkheads are structures built in openings in underground mines to impound water, preventing the water from entering the active mine workings. These structures not only have to be designed to withstand the static, hydraulic pressure, but also the dynamic or seismic pressure, which would be generated by an earthquake. Bulkheads can be considered underground dams. Unlike dams on the surface, bulkheads are often subjected to hydraulic heads that exceed the heights of the bulkheads. Theodor von Karman in 1933, and Westergaard earlier, developed the equation by which the hydrodynamic pressures on surface dams could be calculated. Civil engineering handbooks of today contain this equation. In this paper, using the methodology developed by von Karman and Westergaard, the authors have developed an equation by which the hydrodynamic forces on bulkheads could be calculated when the hydraulic head exceeds the height of the bulkhead.

Jan 1, 2007

By Donelson A. Robertson

Literature was searched and cases of alleged water well damage were investigated. Occurrence of ground water in Appalachia is primarily in low yield, fractured, water table aquifers. Four test sites were chosen based on geographic and geologic diversity. Test wells were drilled at each site and base line data on water quality, static water level, and drawdown characteristics were obtained before surface mining commenced. Blast induced ground vibrations were measured at the surface by the wells at levels up to 5.44 inches per second maximum resultant particle velocity. Measurements made at the bottom wells indicated that vibrations were considerably attenuated at depths of 140 to 160 feet. No direct evidence of change in water quality or well performance was produced by blast vibrations, but removal of downslope support by excavation does cause lateral stress relief which permits the water-bearing fractures to become more open. This additional storage capacity causes the static water level to drop and for well-bore permeability to improve. Static water level recovers if sufficient recharge is available and well performance is improved.

Jan 1, 1980

By Erica Frederickson

"Millennials. Doesn’t the word just make your blood boil? You’ve probably encountered one of those kids who think they know best despite a lack of any real experience.Hi, my name is Erica, and I am a Millennial. We often get a bad rap, sometimes for good reason. But we do have qualities that are often overlooked. For example, I am happy to share with my generation a real desire to make a difference in the world and a commitment to innovation. Does this mean I think we always have good ideas? No – especially not right away. After all, few of us came anywhere near a piece of construction equipment until arriving for our first job, as was the case for me. We may have fancy degrees, but not many of us learned to run a jackleg drill in school.Two weeks after graduating college in 2011, I packed up my bags and moved to New York City to work as a field engineer for Traylor Bros. Inc. on the Queens Bored Tunnels project (Granite/Traylor /Frontier Kemper, JV), part of NYC MTA’s multi-billion dollar Long Island Railroad East Side Access project. It was here I became acquainted with the notorious New York City union workers. Perhaps the greatest challenge of my career thus far was earning the respect of the field supervision and craft workers on this first project.The first time I asked a maintenance mechanic to clean a piece of equipment in accordance with our maintenance protocol I got a flat-out “No.” It was the most powerless I had ever felt. But why should these experienced workers trust a 21-year-old girl with her civil engineering degree and no prior experience? I realized no employee on the job had any reason to listen to me — not until I proved my worth. Fortunately, I arrived on the job site just as we were commissioning the slurry plant for the first tunnel drive. I dove into learning as much about the slurry tunneling process as possible and was able to quickly pick up the ins and outs of running the slurry separation plant. As none of the other engineers or management had first-hand experience on a slurry tunneling job, I soon became the go-to engineer in the slurry plant. No one questioned me if I asked to have something done around the plant after that, or if they did, they quickly learned that I had a convincing answer as to the need for the task. I was even able to play a large role in shaping our slurry monitoring and control methodology."

Jan 1, 2015

By J. J. Dowd

1. The Pittsburgh bed is the most important bed in Marshall County, and virtually the entire production of coal in the county comes from this bed. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 tons per acre-foot of coal in place, were estimated at 3,158 million short tons as of January I, 1954. Of this total, 3,071 million short tons is in beds 28 inches and more thick. Areas in each bed except the Pittsburgh were omitted from the estimate because available data relative to the bed characteristics are too meager to make an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1956

By María Justiniani

Además de los pasivos ambientales mineros que a la fecha oscilan entre los 6900 y 70001 a nivel nacional, existen otras unidades mineras que corren el riesgo de quedar abandonadas o ser paralizadas de forma definitiva, incrementando el patrimonio minero inactivo. Al respecto, su falta de atención, su gestión deficiente y los escenarios limitados que existen para su tratamiento, comprometen seriamente el desarrollo sostenible que se exige para todas las actividades y etapas vinculadas a la minería. En ese escenario, se deben evaluar otras alternativas que permitan un mejor aprovechamiento de dicho patrimonio, que sostenga equilibradamente el desarrollo económico, la protección ambiental y la promoción social.

Sep 29, 2023

By P. K. N. Raghavan

This paper identifies potential technologies for Carbon dioxide abatement from the mining and metal industry with special reference to the Aluminium industry. Mine reclamation could contribute to this effort to successfully reach the greenhouse gas (GHG) emissions reduction commitments for a nation. An overview of GHG production by the mining and metal industry together with a review of principles used to set the context in which specific options for GHG reduction are described. Options for GHG reduction in the mining and metal industry include reforestation, Addition of soil amendments or neutralizing agents, CO2 capture and storage, initiatives towards energy reduction, waste heat recovery and alternative energy use. An analysis and quantification of the potential GHG reduction of potential carbon sinks and sequestration options for the mining and metal industry are provided. Cost estimates for different options are provided. The paper also identifies sources that could fund research regarding GHG reduction options. The paper concludes with recommendations.

Jan 1, 2011

By Christopher Nelsen, Daniel Dobbels, R. Zachary Hollenbeck

Recent major floods have inundated Historic Ellicott City, Maryland, resulting in loss of life and property damage. Howard County, Maryland, has developed the Ellicott City Safe and Sound Plan to mitigate the risk of flash flooding in the Historic District, including a proposed stormwater conveyance tunnel. Challenges to overcome include thick zones of saprolite along the alignment, multiple near-surface structures, and minimal rock cover under an active railroad, while minimizing impacts to the public and historic structures. The project will also pursue recognition through the ISI Envision verification process.

Dec 1, 2022

By R. W. Geehan

The Yellow Pine zinc-lead mine, situated about 3-1/2 miles northwest of Goodsprings, Clark County, Nev., was explored by core drilling during the fall of 1942 and the summer and fall of 1944 by the Bureau of Mines in cooperation with the Federal Geological Survey. The Yellow Pine district was located in 1855. The original claims covering the Yellow Pine mine were located in the following years: Rover, 1892; Hilo, 1897; Bybee, 1900; Radio and Como, 1906. The mine was operated by the Yellow Pine Mining Co. from 1906 to 1929. This company was dissolved in 1935. At a later date, S. E. Yount and the Security First National Bank of Los Angeles, Calif., acquired ownership of the mine. Since 1939, the mine has been operated in a small way by leasers. Production has been at least 175,000 tons averaging about 10 percent lead and 25 percent zinc, with a gross yield of $5,785,174. Virtually all ore produced by this mine consisted chiefly of oxidized zinc and lead minerals and came from long, pipelike shoots in the 100-foot thick Yellow Pine limestone. Ore shoots are sharply defined; elsewhere, the limestone is nearly barren. Numerous faults cut the mine into blocks. Ore is now mined in an open stope, but in the past, large tonnages wore mined in stopes by square-set methods. Ore produced recently was shipped direct to smelters unprocessed; in the past, it was milled by gravity and produced separate lead and zinc concentrates.

Jan 1, 1949

By Ann G. Kim

The U.S. Bureau of Mines applied its mine fire diagnostic method to an abandoned anthracite mine fire site in Carbondale, Lackawanna County, P A. The technique to locate fires in abandoned coal mines and coal refuse piles includes the determination of hydrocarbon concentrations in mine gases, the imposition of an underground gas flow direction, and use of a surface mapping method, to define heated and cold zones in underground coal strata. The heated zones at Carbondale were characterized by elevated methane concentrations. The results of 25 communication tests were analyzed to define 2 large (approximately 100 by 250 ft) and 5 small, isolated heated zones. An approximate correlation existed between the location of the heated zones and areas of anomalous snow melt. The correlation between the results of the diagnostic? test and subsurface temperatures was not significant.

Jan 1, 2010