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By Staff

Minerals contribute to U.S. gross domestic product (GDP) at several levels ? from mining and processing to the manufacturing of Anished products. In 2009, the estimated real GDP of the United States decreased by 2.4 percent compared with, and the estimated nominal GDP was about $14.2 trillion (Table 1). Trends in various sectors of the domestic economy are often reflected in mineral production and consumption rates. In 2009, the continued decline of the housing market was reflected in reductions in the production and consumption of cement, clays, construction sand and gravel, and crushed stone (those mineral commodities that are used almost exclusively in construction). Production of mineral commodities associated with the manufacture of goods for the housing market, such as ceramic tile, heating and air conditioning equipment, paint, plumbing and sanitaryware, roofing, wiring and wallboard also decreased. Declines in auto-mobile manufacturing resulted in reduced production

May 1, 2010

By R. Heiser, J. Vendetti, B. P. Connor, E. J. Haas

"DISCLAIMER The findings and conclusions in this paper are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health. Reference to specific brand names does not imply endorsement by the National Institute for Occupational Safety and Health. ABSTRACT Health and safety indicators help mine sites predict the likelihood of an event, advance initiatives to control risks, and track progress. Although useful to encourage organizations to work together, executing such risk assessments comes with challenges. This paper focuses on one trona mine’s experience in the development and implementation of a field level risk assessment program to help its entire organization understand and manage risk to an acceptable level. Through a transformational process of ongoing support and communication, Solvay Green River fostered a culture of trust and safety grounded in risk assessment, safety interactions, and hazard correction. The application of consistent risk assessment (RA) tools was critical to create a participatory workforce that not only talks about safety, but actively identifies energies that contribute to hazards and potential incidents. In this paper, reflecting on the mine’s process of RA implementation provides examples of likely barriers that sites may encounter when trying to document and manage risks. As discussed, consistent efforts to establish a participatory risk management program are worth the initial struggle to ultimately reduce incidents. INTRODUCTION Work-related health and safety (H&S) incidents often account for lost days on the job, contributing to organizational/financial and personal/social burdens [1-2]. Accompanying research demonstrates that risk and ambiguity around risk contribute to almost every decision that individuals make throughout the day [3-4]. In response, understanding individual attitudes toward risk has been unquestionably linked to predicting H&S behavior [5]. Although an obvious need exists to identify more comprehensive methods to assess and mitigate potential hazards, some argue that risk management is not given adequate attention in occupational H&S [6]. Additionally, research suggests that a current lack of knowledge, skills, and motivation are primary barriers to mitigating workplace risks [3-6]. Therefore, enhancing knowledge and awareness around risk-based decisions, including individuals’ abilities to understand, measure, and assign levels of risk to determine an appropriate response, is increasingly important in hazardous environments to predict and prevent incidents. This paper focuses on tailored approaches to field level risk assessment (FLRA), measurement, and common barriers to participating in such activities. The authors use a trona mine in Green River, Wyoming, as a case study to illustrate how the organization overcame widespread and site-specific challenges to implement a proactive risk management program. By discussing the mine’s tailored FLRA program, this case study contributes to the literature by first, providing examples of critical components that need to be in place to ensure successful risk management and second, context for continuous quality improvement that can foster a higher level of trust and empowerment on site."

Jan 1, 2017

By G. Morin, F. Chiesa, B. Duchesne

The Quality index is a useful tool allowing to assess the metallurgical quality of aluminium AlSiMg foundry alloys (A356/357). Its value is calculated from the ultimate tensile strength and elongation; it increases with the metallurgical quality of the casting, i.e. with finer dendrites, lower microporosity and inclusion count and lower iron content. This Quality index does not depend on the degree of temper applied during the heat treatment (aging time and temperature). After defining the Quality index, it will be explained how it can be predicted from the knowledge of the local solidification conditions obtained from modelling. The paper will then present four case studies of castings for which the prediction of the Quality index by modelling was made. These case studies from different authors will involve the three most common casting processes used for producing high integrity aluminium castings, namely: sand casting, permanent mould casting and investment casting (lost wax). In all cases, the accuracy of the prediction will be assessed by comparing the predicted Quality index distributions to the experimental values based on the published measured values of the local tensile properties.

Jan 1, 2006

By A. S. Choudhary

Most of the coal reserves in India are of drift origin and have very poor washability characteristics and a high level of near gravity materials. At least 30 new coal wash plants are expected to be set up in the next 5years.In such a scenario, adequate sampling followed by sink float test work for washability analysis becomes very critical for designing these new plants. For coal sampling purpose, stipulations of different standards are sometimes formidable and on the border of ?impracticality?; sometimes are self contradictory in terms of gross sample weight vis-a-vis minimum number of particles required in each size fraction and in each relative density fraction and also the minimum mass in the latter. Validation of the generated data is another important aspect of washability analysis. These issues can easily be addressed by using straight forward mathematical relationships, well known RR plots and by using simple MS Excel tool, etc.

Sep 1, 2012

By J. C. Irvine

Meramec Mining Company, a joint venture by Bethlehem Steel Corporation and St. Joe Minerals Corporation, is engaged in the mining, concentrating, and pelletizing of iron ore from the Pea Ridge Mine located near Sullivan, Missouri, about 70 miles southwest of St. Louis. The orebody was delineated in the mid-1950's by St. Joe during an exploration program to discover new lead orebodies. An airborne magnetometer survey which was run by the U. S. Geological Survey, the Missouri Geological Survey, and several min¬ing companies was published in 1950 and showed an anomaly in the Pea Ridge area. Test holes drilled in 1953 and 1954 revealed the presence of a large orebody of probable commercial significance; additional drilling in 1956 and 1957 provided confirmation of this. Meramec Mining Company was incorporated in 1957 and shaft sinking began in the latter part of that year. The Pea Ridge orebody lies under about 1300 feet of sediments. It is tabular, about 2600 feet long and up to 600 feet thick, and lies in an approximate east-west delineation. The orebody dips about 800S and is of unknown depth. The ore is primarily high grade magnetite with smaller zones of specular hematite, The Pre-cambrian wall rock is rhyolite porphyry. The mine is serviced through two concrete-lined shafts, 19 feet 1 inch in diameter and 2500 feet deep. No. 1 shaft, equipped with an "A" type head-

Jan 1, 1972

[1.1. The provisions of this code are minimum provisions and are designed to minimize hazards to life and property in and about underground coal mines where electrical equipment and circuits installed used. They indicate the Steps necessary in the selection, installation, operation, inspection, and maintenance of electrical equipment and circuits to obtain proper safeguards in reducing electric shock, fire, explosion and other hazards. Surface as well as underground installations were considered in formulating the code and, unless otherwise stated, each provision applies equal to both underground and surface installations. This code does not apply to buildings and installations not directly connected with mining operations, nor does apply to strip-mining operations.]

Jan 1, 1952

By Augustus Locke

I WISH to urge on this Committee the task of evaluating mining geology. -My motive is as follows: It, is a. duty of the Institute from time to5 time, to establish the social perspective of the professions grouped within it, not simply to promote their use, but to determine with engineering definiteness their true powers and functions. This becomes the delegated duty, therefore, of this committee in respect to geology. Be- cause my own subject is mining, I shall confine my remarks to mining geology. But I believe that the evaluation should be made to include all of that geology termed economic. The perspective for such evaluation is shown in the nature of the public support given to geology. The federal Geological Survey, the leading organization on the economic side, is actuated by the zeal of a small group of devoted professionals who consider its work valuable, ' It proceeds, however, on a starvation ration of appropriations, and that implies that neither the corporations, the voters nor the vote getters consider it important. Altogether, in' the public consciousness, geology is negligible. That, at the same moment, .the profession should act with full confidence, while everyone else should act' with opposite motives, is not fitting. For us, as a committee, to remain incurious regarding such a disparity of beliefs is quite impossible.

Jan 1, 1931

By H. W. Kilau

The Bureau of Mines used a high-temperature rotational viscometer to test basic oxygen furnace slags to determine fluorspar requirements and to evaluate colemanite and fused boric acid as substitute fluidizers. A continuous technique of viscosity measurement was adapted to better determine the viscosity-temperature profiles of volatile fluorspar slags. Criteria used for estimating slag fluidizer effectiveness were (1) the apparent solidification temperature, and (2) the temperature range of slag crystallization. Colemanite and fused boric acid in high-basicity slag were superior fluidizers to fluorspar when compared on the basis of boron versus fluorine concentration. Fused boric acid was nearly equivalent to ceramic-grade fluorspar when compared on a simple weight basis, while colemanite was inferior to fluorspar. Fluorspar slags volatilized fluorine during viscosity testing. Colemanite and fused boric acid slags were stable, no boron losses being detected. A fluidizing limit was found for fluorspar at 2.9 percent fluorine concentration; higher concentrations impaired viscosity and caused foaming and crusting of slag. Concentrations of boron up to 4.4 percent resulted in very fluid slags with no fluidizing limit.

Jan 1, 1978

By A Hatt

This paper presents a case study of characterisation work undertaken at a greenfield exploration project to provide engineering and OH&S inputs for the design of a ventilation system. The paper discusses how comprehensive early characterisation of the ambient surface and underground environment including aspects related to heat, dusts, strata gas, and geologic/mineralogical factors enables incorporation of the right ventilation and non-ventilation controls at a study level to mitigate the risks identified.

Oct 12, 2022

By AIME AIME

A PERIOD of business depression and falling prices always raises questions as to the possible responsibility of the monetary or banking system. This is natural enough, for it is agreed that the supply of money or credit is a very important factor in modern business and in prices. However, it is far from being the only important factor. One of the chief merits of the gold standard is that under its workings the supply of currency and credit is regulated automatically to the masimun extent, in- stead of by the control of any arbitrary authority. The supply of new gold comes from the mines, and mining is free. It is distributed among the countries by the currents of trade and the play of economic forces, with the general result that the distribution tends to be in accordance with the economic development of the countries and their ability to use it or command it. Inasmuch as the accumulated stock of monetary gold is very large in comparison with the annual additions, the total avail- able supply changes but little from year to year, and it may be assumed that price-changes that are properly chargeable to gold will take place gradually rather than suddenly.

Jan 1, 1930

By Owen Matthews

THE property of Cochenour Willans Gold Mines, Limited, is in Dome township, Red Lake area, northwestern Ontario, a hundred miles north of Kenora and close to the Manitoba border. 'Planes of Canadian Pacific Air Lines, Limited, serve the district daily, except Sundays, from Kenora, Ontario, and Lac du Bonnet, Manitoba, passengers being trans-ported from Winnipeg to Lac du Bonnet by car. Freight is handled by the Patricia Transportation Company. It is brought in from Hudson, Ontario, on the Canadian National railway, in summer by water and in winter by tractor trains over the frozen lakes. The first staking on the property was done during the 'rush' of 1926 and 1927 by William M. Cochenour, and on April 30th, 1928, a syndicate was formed, taking in claims of W. M. Cochenour and Dan Willans and H. G. Young. Surface trenching was carried on almost continuously until 1934. In October, 1932, Ventures Limited took an option on the property, and in December of that year they carried out an extensive diamond drilling programme, but considering the results did not justify further work, they relinquished the option. In July, 1934, further surface work was carried out under the supervision of W. P. Mackle and, on the strength of his report, Noah Timmins Incorporated took an option on the property and agreed to make an initial expenditure of $100,000 on development work. This was carried out under the direction of Hollinger Consolidated Gold Mines and included the sinking of a shaft to a depth of 165 feet, establishment of a level at the 150-foot horizon, and some 1,900 lineal feet of drifting and cross-cutting. The results obtained from this work were not considered of sufficient promise and the option was terminated in August, 1935. Mr. Cochenour then approached Alex Mackenzie and associates, and the present Company, Cochenour Willans Gold Mines, Limited, was organized on April 9th, 1936, and sufficient money was raised to continue operations. Under the direction of W. P. Mackle, the shaft was deepened and a second level was established at the 275-foot horizon; but, due to several adverse reports by outside engineers, it was found impossible to raise sufficient money to carry on the work and operations were suspended in December, 1937. In January, 1939, an agreement was entered into with Gold Eagle Gold Mines for the milling in their plant of some Cochenour ore. A total of 4,959 tons was treated, and the results were so encouraging that further finances were raised by C. A. Gentles & Company, of Toronto. Following further development in the mine, it was decided to erect a mill. Construction was started on September 1st and the mill was turned over on November 29th. The first gold brick was poured on December 23rd.

Jan 1, 1942

By Won C. Park

Experiments showed changes in the mineral content of dolomitic oil shale at temperatures and exposure times which bracket conditions encountered during in situ retorting. Laboratory results correlate with cores from a spent in situ retort at Occidental's Logan Wash test site at Garfield County, Colorado. Dolomite, CaMg(CO3)2, decomposes rapidly to form periclase, MgO, calcite, CaCO3, and CO . Both calcite and periclase are intermediate products that can be stabilized by CO atmosphere at lower temperatures, while steam accelerates the formation 2 of silicates. The decarbonation of calcite appears to involve a direct reaction with both quartz and periclase in forming these silicates. Decarbonation preceeds the formation of akermanite, Ca2 MgSi 207, and diopside, CaMgSi 206, within several hours of heating and is followed by the nucleation of forsterite Mg2SiO4, and monticellite, CaMgSiO4. Under in situ retorting conditions, akermanite and diposide are the major minerals above 800°C. Equilibrium is not attained within 200-300 hours. In situ retorting temperatures above 800°C for extended periods of time should reduce potential ground water leaching by the formation of silicate minerals. These silicates are less soluble than free lime, magnesium or alkali oxides. There is a corresponding decrease in the natural pH of these silicates from approximately 12 down to 7.5 to 9:

Jan 1, 1981

By R. L. Derick

The Orchard Valley Mine, a large underground coal mine located in western Colorado, experienced a major mine fire during an idled Sunday on June 1, 1986. This mine had extensive problems with spontaneous combustion near the coal outcrop. Spontaneous combustion has been determined to be the probable cause of that fire. Preparing for a mine emergency was an on-going task. Once the emergency occurred, much of the preparation work was implemented and aided in controlling the situation. Later, the successes and shortfalls that arose from that emergency were analyzed for future course of action. This paper summarizes the activity that led up to the major fire, the handling of that emergency, the lessons learned, and the changes implemented.

Jan 1, 1993

By Gabriella Vaschetti, Pascual Perazzo

A paper presented at Perumin 35 in 2022 described the concepts and a state-of-the-art system with extruded curbs and PVC anchor wings, adopted among others at the first four stages of Las Bambas tailings dam in Peru, discussing how upstream geomembrane water barriers can mitigate the numerous issues, including environmental aspects, of tailings dams’ design and operation. This paper, beside presenting a summary of what has been carried out so far at Las Bambas, amplifies the subject, presenting the results by means of the data of the leakage monitoring system, showing that the flow monitoring data at the downstream toe are seasonally consistent, and in alignment with design predictions.

Sep 29, 2023

By ALEX. S. THOMAS

HOWEVER good a furnace may be in regard to design, etc., or however excellent in the quality of the gas used, a suitable heat for the successful working of the metal cannot be obtained unless the melt be coated with a proper quantity of slag. This coating may be excessive or it may be deficient in quantity. The right degree of heat is the essential condition of successful working, for the quality of the steel made is never very good when the metal is allowed to simmer in the furnace for an excessive period, and this heat cannot be obtained if the metal is not protected by a proper covering of slag. This is not only to prevent the metal being over-oxidized and wasted, but also to prevent the metal being chilled when exposed with only a thin covering of slag. The slag may be obtained in either of two ways : 1, naturally, by the presence of sufficient silicon in the iron used, to unite with iron oxide to form a staple slag ; or, 2, by the addition of slag or free silica. In the first case the slag is formed naturally by the action of the oxygen in the flame - i.e., the oxidizing atmosphere of the furnace-on the silicon in the metal when melting. The charge then melts, as it is termed, "thick," and protects the banks from being cut. If too much silicon be present, however, and an excessive quantity of slag be formed, it will be found to be rather infusible, and unless care be taken to add the oxides quickly and follow the furnace up-thus rendering the slag more fusible by the extra iron oxide-the furnace bottom is liable to be pulled up. In such cases the author has frequently been able to warn

Nov 1, 1906

By J. Pasini

The Bureau of Mines has investigated novel methods of stimulating petroleum production from reservoirs in the Appalachian Region. An important consideration in applying stimulative production methods is the control and removal of solid precipitates from the boreholes of production wells. Where paraffin-base crude oils are produced, as in the Appalachian Region, the accumulation of paraffin may be particularly troublesome. Paraffin deposition is a major production problem that has confronted the petroleum industry for many years. Although considerable effort has been expended by industry and government, a suitable solution has not been found because of the individuality and complex nature of the deposits. Remedial methods used to prevent or remove paraffin fall generally into four classes: (1) Chemical, (2) physical, (3) operative, and (4) combination. Each class has many subclasses that apply to particular problems in different oil- producing areas. Recently, chemical inhibitors and the sonic pump have assisted operators in preventing and removing paraffin deposits. Because these methods are relatively new, their degree of application has not been completely evaluated.

Jan 1, 1963

By Edward H. Robie

THE registration badges gave out, there were not enough programs, the Pioneer Hotel's rooms were insufficient, and some hundred applicants for banquet tickets had to be turned down at the Institute's Regional Meeting in Tucson, Nov. 1-5. Minor inconveniences these, however, occasioned by the fact that, optimistic as they are in Arizona, about half again as many partook of the week's activities as were expected. For this, the local program committee can be blamed-both the technical and social features were too attractive in quantity and quality. Seriously speaking, though, the Institute has probably never had a more successful Regional Meeting than this one. It being the first that has been held in Arizona in 22 years, no effort was spared to make it the distinctive gathering that it was.

Jan 1, 1938

ILZRO sights are locked securely on the targets of the expanded applications and ever-improving quality in the major market for zinc-coated steel. A wide range of ILZRO-sponsored research projects examine issues of formability, paintability, and corrosion resistance for traditional hot-dip galvanising, electrogalvanising, and ILZRO's own proprietary zinc coating, Galfan. Recent research has focussed on the on the interaction between Galfan and different substrate steels to determine optimum combinations for different applications. ILZRO enjoys an evolving role in providing the connection between research laboratories and marketing divisions through supporting research and services for the Galfan Technical Resource Centreò(GTRC) and the recently formed North American Galfan Development Authority (NAGDA). GTRC has just produced a new problem-solving manual that provides a comprehensive source of hands-on solutions for the many Galfan licensees throughout the world, and should contribute substantially to the reputation of Galfan as a consistently top-quality steel-coating product. Meanwhile, NAGDA is advancing the market with new advertising for Galfan based on superior corrosion-resistant qualities proven through ILZRO-sponsored research. Practical manufacturing issues remain at the forefront of ILZRO priorities, with research emphasis on cutting and welding zinc-coated steel to provide direct assistance towards improved product quality and a more secure market. Moving to the arena of die casting, when the specifier looks to zinc to fill a design need, ILZRO-sponsored research projects provide comprehensive documentation on metallurgical characteristics for every zinc alloy under almost any imaginable application. On-going ILZRO-sponsored research is integrating this wealth of data with sophisticated computer programs that model die-casting designs with ever-increasing accuracy, as other ILZRO projects lay the market groundwork for zinc in applications ranging from vibration damping to electromagnetic shielding.

Jan 1, 1993

By The Staff

"THE Wabana iron ore mines, owned and operated by the Dominion Steel and Coal Corporation, Limited, .are on Bell Island in Conception bay, on the east coast of Newfoundland. Mining began on surface in 1895 and, although open-pit work is still done on a small scale, the entire output may be considered to•be derived from extensive submarine workings. In 1958 the average daily production of hematite ore was close to 12,000 tons, almost all of which was concentrated in a heavy-media plant. SUMMARYThe character, occurrence, and extent of the submarine bedded deposits enabled early operators to meet prevailing market demands with the minimum attention paid to exploration. Mechanization of the mine and the pressure for sustained high tonnages since 1955 have emphasized the importance of an expanded exploration and development programme.A serious handicap has been the impossibility of utilizing normal diamond drilling methods to explore ore conditions in advance of mining faces. Drilling between tl1e bedded zones has been done but the major difficulty has been to delineate ore reserves in the lower bed, which has the greatest ore potential of the three mineable seams."

Jan 1, 1960

By J. J. Laffin

In the pursuit of comfort and safety, the wonders of science have given us controlled heating and cooling, thus enabling us to enjoy all the aspects of present-day living to an extreme never previously •envisaged. Man's attempt to conquer the elements largely involves con-trolling the temperature around him. Without having conquered this aspect, his body energy would be consumed in trying to maintain physical comfort, rather than being invested in the explorations which have resulted in man's control over the forces of nature. The indirect methods used to obtain the most agreeable temperature environment were developed because of the natural tendency to strive for increased safety, convenience and comfort. Until the twentieth century, when heat generated by atomic fission became a reality, man's only source of heat, except for that of the sun, came from his discovery of fire.

Jan 1, 1962