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By ROBERT B. COONS

SELECTIVE SERVICE must meet three important demands for man power: (1) Activities concerned with production of war goods. (2) The armed forces. (3) Civilian activities and institutions the continuance of which are essential to maintaining the structure of our American democracy. In the above enumeration of demands I have placed everything, including most of our most prized possessions and activities, after the demand for men for war production and the armed forces. To establish an order between the latter two is difficult. For the time being, at least, the Selective Service policy is to make sure that we avoid the risk of "too little and too late." No soldier, sailor, or marine should be sent from these shores to risk his life without the assurance of having a gun, clothes, food, and medical supplies. Therefore, the premium is now being placed on man power for war production and in our process of selection no stone is left unturned to see that our agencies are fully informed of the needs of war production. Our procedures set up recourses for employers of war-production man power so that their activities need not be disrupted, at least not until they have had time to train replacements.

Jan 1, 1942

By William J. Miles

The major health hazard from exposure to crystalline silica historically has been silicosis. Silicosis is the scarring of the lung from excessive exposure to crystalline silica. It has been recognized as an occupational disease for over two thousand years, since early Greek physicians noted the respiratory problems of miners, stonecutters, and quarrymen who were exposed to excessive quantities of mineral dust. During the industrial revolution, the incidence of the disease was greatly increased by the use of machinery which increased dust levels. Subsequently, the need for dust control was recognized and dust control measures were instituted. Silicosis is characterized by progressive breathlessness on exertion and develops over the course of years. X-ray images of the lungs show progressive scarring of the lungs. The symptoms are related to the amount of exposure to crystalline silica and the years of exposure.

Jan 1, 1990

By W. E. Selnes

Introduction In 1938, a survey conducted by the Ontario Mining Association revealed a rather startling fact. Injuries incurred in chute pulling were more numerous than those from any other single cause. This report prompted Mr. W. B. Paton, then Inspector of Mines for Manitoba, to make a similar survey of the mines of his Province. It indicated that, in Manitoba mines, chute accidents ranked second only to those from falls off roofs and sides. Why has the mining industry been so slow to recognize the dangers of chute pulling? A partial answer may be the lack of any systematic classification of accidents according to their real cause. The result has been to attribute to other causes injuries which were a direct outcome of chute pulling, and, indeed, has made it difficult to analyze accidents in the industry as a whole. Perhaps, too, because chutes are generally located in the comparative safety? of the drifts, there has been a tendency to consider the occupation as not very hazardous. Not until enough statistics were obtained on this particular task could it be appraised correctly. The Mining Association's survey has been most helpful, and latterly the industry has done a great deal toward analyzing the causes of chute accidents and toward determining an effective means of overcoming them. Much, however, remains to be done. An effort will be made in this paper to outline methods which have been found successful in materially reducing the number of injuries. Qualifications of the Chute Puller First of all it must be realized that chute-pulling is a specialized occupation. The men require proper training for the job, just as in other mining operations. Care must, therefore, be taken to choose persons whose qualifications fit them for the job. Chute-pulling is an integral part of the general mining operation and cannot be considered as isolated from the tasks of other workers. One of the essential qualifications of a chute-puller is a sufficient knowledge of mining operations to appreciate the effect his work will have on the safety of others in the vicinity. He must take the necessary precautions, by verbal warnings, by placing barricades and signs, or by personally guarding the chutes, to prevent accidents to fellow workers.

Jan 1, 1947

By J. E. Murphy

The Bureau of Mines developed a hydrometallurgical method for recovering mercury metal from mercury sulfide concentrates. Sulfide flotation concentrate from the McDermitt Mine was leached in a cupric chloride solution at 80° C. The redox potential of the solution was maintained at 850 mV during leaching by chlorine sparging. Mercury extractions exceeded 99 pct in 3 h of leaching. After leaching, the pH of the solu-tion was increased from 1 to 4.5 to precipitate copper as atacamite. The pregnant solution typically containing 100 giL Hg was sent to elec-trolysis to produce high-purity mercury metal and chlorine for recycle. In a 200-A electrolytic cell operated for 24 h, current efficiency was 99 pct and the energy requirement was 0.9 kW·h/lb of mercury produced. Mercury removal from the waste stream was also investigated. Iron or zinc cementation, sulfide precipitation with H2S, and activated carbon adsorption all decreased the mercury concentration from 10 giL to 0.01 mglL, which is less than the Environmental Protection Agency limit on wastewater of 0.02 mg/L.

Jan 1, 1987

By Y. -J. Park, K. -H. You, Y. -T. Choi, Lee. H. -W.

Many large caverns are being constructed in great depths in Korea mainly for the storage of oil and LPG. These caverns are mostly located near the port where rock conditions are reasonably good. In some instances, the horizontal stress is very high and endangers the stability of the cavern. The purpose of this study is to assess the stability of large caverns excavated in a rock mass with high horizontal stress where Ko value is close to 3. Result shows that stress exerted in the shotcrete at crown exceeds allowable value when the 3rd bench is excavated. Also found is the tensile failure of shotcrete near the boundaries between benches. In Korea werden viele grosse Kaverne fuer Aufbewahrung vom Oel und Fluessiggas in grosser Tiefe gebaut. Am Meisten befinden sich diese Kaverne in der Naehe von Haefen, wo der Fels gute Verhaeltnisse zum Bauen einer Kaverne besitzt. In einigen Faellen ist die Horizontalspannung sehr gross und dadurch wird die Stabilitaet vom Kaverne gefaerdet. Der Zweck dieser Arbeit ist die Stabilitaet des im Fels gebauten grossen Kavernes mit hoher Horiaontalspannung zu schuetzen, wo Ko-Wert sich auf 3 naehrt. Die Ergebnisse zeigen, dass die Spannung im Spritzbeton an der Krone den zulaessigen Wert ueberschreitet, wenn das dritte Bank ausgegraben wird. Im Bereich des Spritzbetons zwischen Baenke wurde das Zugversagen festgestellt. Des larges cavités nombreuses sont en train d’être construites en grand profondeur en Corée prin-cipalement pour le stocage du pétrole et LPG. Ces cavités sont pour la plupart situées près de la porte oú les conditions des roches sont résonablement bons. En quelques cas, la contrainte hori-zontale est trés haute et met en danger la stabilité de la cavité. L’objet de cet étude est d’estimer la stabilité des large cavités excavées dans une masse de roche ayant une haute contrainte horizontale oú la valeur de Ko est proche à 3. Le résultat montre que la contrainte exercée dans le shotcrete à la couronne dépasse la valeur admissible quand le troisième banc est excavé. En plus une faillite en tension du shotcrete près de la frontière entre des bancs est trouvée.

Jan 1, 2003

By Karl Gugel, Dante Garcia, Peter Czel, Eduardo Nunez, Joshua Morales, Boris Sullcahuaman

Real-time operational excellence is achieved through the seamless integration of various components. Key aspects include precise instrumentation, real-time data collection, data analytics, and an efficient optimization platform. Additionally, to ensure success, the real-time optimization platform must be incorporated into the site’s internal process control system (Nunez, 2022). This paper provides an overview of practical lessons and best practices for autogenous (AG), semi-autogenous (SAG), and ball mill (BM) grinding. It highlights the implementation of advanced instrumentation, specifically vibration sensors on the rotating mill shell. The paper also delves into the application of advanced analytics necessary for generating new measurements that accurately represent real-time grinding activity in the mill. These Advanced Analytics Measurements (AAM) are compared with well-known grinding curves to determine the optimal grinding point. The discussion focuses on key industry opportunities using real-time mill shell vibration results to derive new correlations and optimize the grinding process.

Feb 1, 2025

By Richard W. Brummett

Problems in new strip mine development is a subject that could require several days to cover adequately. Coupled with the fertile imagination of television writers, we could probably expand it into a series rivaling Gunsmoke in longevity with just as many shootouts at sundown. It would-of course-be subject to a high Neilson Rating. To bring the subject into perspective, we will limit the comments to a general discussion covering western strip coal developments. Stimulated by increased demand for low sulfur coal, surface mineable western coal operations began a shift into high gear approximately four years ago. Then came last year's "energy crisis" that increased the pressure on coal development not only in the west, but nationwide. Several eastern power plants having dual oil and coal burning facilities were directed to discontinue using oil. Also, a number of new south and southwestern power plants scheduled to burn natural gas or of I commenced an ordered conversion to other fuels, namely, coal. The involved utilities with reserve positions accelerated their planning while others began the search for long-term commitments from coal producing companies. In addition, announcements were made for proposed mine mouth coal gasification projects in New Mexico, Wyoming, and North Dakota.

Jan 1, 1974

By R. L. Grayson

Using powerful database management software, nested-field analysis and microanalysis of narratives have been made of West Virginia accident data, resulting in a new approach for targeting and prioritizing safety interventions by county, mine size, specific mine, job title, type injury, etc. and combinations of these parameters. The analyses have been useful in focusing training and discussion sessions on specific work problems, trends, conditions, and situations for targeted groups of miners. Application of the technique will be presented in this paper, along with comparisons of various mine performance measures.

Jan 1, 1997

By Keith L. Harris

Surprisingly, real gross national product (GNP) surged at a seasonally adjusted annual rate of 4.3% for the first quarter of 1987 according to preliminary estimates made by the Department of Commerce, the highest rate in 3 yr and significantly above the revised fourth quarter 1986 rate of 1.1% (table 1). The spurt, however, was caused by an unusual $59.5 billion rise in inventories, mostly cars and trucks, and there was little support from other sectors of the economy. Motor vehicle inventories rose as consumers continued to tighten their purse strings--consumer spending declined 0.4% for the second quarter in a row. Nonresidential and residential fixed investment and government purchases of goods and services were also down from the previous quarter. The increasing cost of energy was the major factor in the jump to 3.696 in the rate of inflation, as measured by the fixed-weighted price index for GNP, and rising inflation also helped put a damper on consumer spending. The underlying good news was that the trade deficit shrank for the second quarter in a row as imports declined at an annual rate of 11.1%. Also, profits in the manufacturing sector rose strongly in the fourth quarter, and for the first time in 9 quarters, the primary metal industries became profitable (table 1). If one discounts the anomalous inventory growth, the bottom line is that the economy continues to grow at close to the expected 2.5% level experienced over the past 2 yr. Of concern over the next several quarters, though, is the impact of the large over- hang of motor vehicles inventories on the economy. EMPLOYMENT The civilian unemployment rate declined to 6.636 in March after remaining at 6.7% for the previous 3 months. Employment continued to expand in February and March, although growth was significantly slower in March than in previous months. The manufacturing sector, however, lost 24,000 jobs in March after gaining 46,000 in February. Three-quarters of that gain came when striking workers at USX Corp. and Deere & CO. returned to their jobs. Employment in the manufacturing sectors of direct interest to the mineral industries has generally been increasing for at least the last quarter, while worker hours for these sectors have been on the upswing since April 1986 (figures 1 and 2).

Jan 1, 1987

By S. C. Ells

Within the Dominion of Canada occurrences of petro-liferous shales have been known for many years. Nevertheless, with the exception of a comparatively brief period, Canada has had to depend largely on foreign sources for its supplies of crude petroleum and petroleum products. Attempts were made to retort local shales in 1859, near Collingwood, Ontario, and again in 1862, near Baltimore, New Brunswick. In each instance these attempts were abandoned owing to the rapidly increasing production of well petroleum from the newly discovered pools of western Ontario and Pennsylvania. Now, after a lapse of nearly sixty years, attention is again directed to the commercial value of Canadian shales as a possible source of crude petroleum. Province of Nova Scotia: The principal deposits of oil-shales occur in Pictou and Antigonish counties and have been known for more than 60 years. During the three years following its discovery, several thousand tons of a particularly rich sub-variety, known as stellarite (stellar coal or oil coal) was mined near Stellarton in Pictou county. It is stated that stellarite yielded upwards of 10,000 cubic feet of 36 candle gas, and that selected samples gave a yield equivalent to 170 Imperial gallons (204 U.S. gallons) of crude petroleum per ton. The average petroleum content of a cargo shipped to Boston was 48 Imperial gallons (57.6 U. S. gallons) and the associated shale or 'bat', gave a yield of 39 Imperial gallons (46.8 U.S. gallons). Part of the above output was shipped to retorting works in Boston and in Portland, and part was mixed with bituminous coals for the enrichment of illuminating gas. Following the discovery of well petroleum in Ontario and in the United States, the mining of stellarite ceased.

Jan 1, 1925

Commodities statistics and other information are available through the following three systems: Internet Access: To access the USBM Gopher server on Internet, connect to: gopher.usbm.gov port 70, using gopher client software. Or contact the Systems Administrator for technical questions: Matt Klevemann, 412-892-6499 (klevemmc@miner.usbm.gov) These USBM materials are available on Internet, with more to come in the future: Publications and other research findings, including this bimonthly publications list, newsletters, tech transfer updates, environmental technology research, health and safety information. USBM software products Media materials and speeches. Mines Data: Computer bulletin board. Log on via modem through 202/501-0373, or call 202/501-0406 for technical assistance. Mines FaxBack Return fax service. 1. Use the touch-tone handset attached to your fax machine's telephone jack. (ISDN [digital] telephones cannot be used with fax machines.) 2. Dial 202/219-3644. 3. Listen to the menu options and punch in the number of your selection, using the touch-tone telephone. 4. After completing your selection, press the start button on your fax machine.

Jan 1, 1995

By A. C. Fieldner

All technical facilities of the Bureau of Mines have been geared for more efficient use and conservation of mining equipment, developing plans for safety, improving the quality of coal through better methods of preparation, studying the problems of coal storage and utilization, and extending the uses of coal5/ for the war and postwar economy. The Bureau is now analyzing all of the coal purchased by the Army and much of that required by the Navy. Work on boiler feed water was doubled over last year to meet the increased demand made by the War Department for protecting vital boiler plants in many new camps and defense plants. Progress has been made in safely storing coal to reduce dangers of spontaneous ignition to a minimum and to preserve coking power. Mixtures of oil and coal to be used as a substitute fuel have been investigated. Technical service on the conversion of plants to other fuels has been given to government agencies and private consumers. The possibilities of making motor fuel,

Jan 1, 1944

Philip Argall, Denver, Colo. (communication to the Secretary) : Mr. Rickard expresses regret that I have not given more extracts " from the fresh leaves of nature's open book." The quotations used by me in argument were all from nature's open book, and by authorities recognized in the scientific world as being able to decipher nature's unwritten pages, if not lay bare her inmost secrets. The study of -nature should be preceded by a knowledge of her laws. Natural science is but the summary of the observations of the past or an organized and accurate knowledge of the order in which things have been observed to happen. One who ignores the 'knowledge of the past or despises that of the present and approaches nature's open book with a virgin mind but too often finds her

Jan 1, 1895

By R. E. Nelson

The Alton Coal project, located in south-central Utah, lies at one point just over six miles from Bryce Canyon National Park. This region of the southwestern United States has been called the "Golden Circle" of national parks and monuments. Can a mine be inserted into this region so that it does not intrude on this spectacular landscape? The Alton Coal Project is a proposed surface coal mine designed to serve as the fuel source for the Harry Allen Power Plant, a 1,000 megawatt generating station planned for a site 25 miles northeast of Las Vegas, Nevada. The mine and the power plant will be connected by an underground pipeline through which coal will be transported in slurry form.

Jan 1, 1988

By Frank B. Fulkerson

Three of the five primary aluminum producers in the Pacific Northwest have facilities in the region to make aluminum mill products. Only one of the three, however, produces a variety of shapes and forms. The principal reason for the lag in development of an aluminum mill products industry was found to be transportation cost. The long range outlook is for expansion, based mainly on growth of the western market for aluminum used in construction, containers and packaging, electrical applications, diesel trucks, mobile homes, and irregation pipe. Consumption of western aluminum mill products in 1985 is projected at 1.1 million tons, compared with estimated consumption of 250,000 tons in 1961.

Jan 1, 1965

By Gerald R. Smith

Because of continuing concerns regarding the effects of cumulative quantities of materials in the environment, the Bureau of Mines has initiated a series of studies to evaluate, to the fullest extent possible, all aspects of the materials flow sequence fur selected commodities. Although tungsten and its compounds do not pose a significant health hazard to the environment, they do represent valuable resource materials to which appropriate conservation considerations must be given. The present study includes a description of recent trends in the consumption, loss, and recycling of tungsten-containing materials in the United States during the period 1974 to 1991 and an estimation of the cumulative loss of tungsten to the environment since 1910. Obsolete tungsten is recycled primarily as cemented tungsten carbide components that have been used in cutting and wear-resistant applications. The quantity recycled, as a of annual U.S. consumption of tungsten, was estimated to have increased from 10% in 1974 to 341a in 1991. An estimated 58% of the 148,000 metric tons of primary tungsten consumed since 1910 was lost to the environment through means such as dissipation, discard, and dilution.

Jan 1, 1994

By F. T. Cawood, M. A. Jooste

This paper describes the survey monitoring processes at Venetia, which are discussed under visual inspections, ad hoc investigations, system monitoring and slope stability radar monitoring. This is followed by a description of the main survey monitoring methods. The next section briefly states typical problems, i.e. the atmospheric corrections required to adjust total station distances, maintenance of the system and management of the monitoring process. The paper ends with some important lessons that could be applied to similar monitoring programmes. These lessons are firstly, communication is most important, process a vital part of the system, a champion must take responsibility for the programme and system planning ensures that the monitoring results are needs driven.

Jan 1, 2006

By B. J. Moore

This publication contains analyses arid related source data for 274 natural gas samples from 20 States. Of the total samples, 269 were collected during calendar year 1985; the reminder were collected earlier, but releases granting permission to publish were not received before 1986, All samples were obtained and analyzed as part of Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free market economies. This survey has been conducted since 1917. The analyses published herein were made by mass spectrometer and chromatograph.

Jan 1, 1987

By Jim McKinley

With a growing number of mines reaching closure and seeing closure costs materialize, regulators, lenders, and banks are observing projects that fail economically by miscalculating these costs. Mine closure costs are often categorized as a type of liability which is defined as the money owed by the company to offset effects from the project, and the money available to pay for those debts (e.g., bond). Often, decisions made before Day 1 of mining (e.g., co-disposal, dry stack tailings, waste segregation) can significantly change the bond calculation. Once the bond is calculated and funded, operators are encouraged to conduct closure research and use applied science for progressive bond release prior to final closure. However, this author has observed few instances of financially significant progressive bond release, as there are typically no robust procedures for bond return, either before or during closure activities. As a result, many companies decide that entering a state of Care & Maintenance (C&M) is less risky than attempting to fund closure activities with an unknown bond return mechanism. Although perhaps less risky in the short-term, the primary long-term risk with entering C&M is that it increases the chances of the bond not covering the cost of closure and the chances of the government/regulatory agency inheriting the mine closure. Bonds are typically reevaluated on a regular cycle (e.g., five years) so every mining company goes through this financing challenge eventually.

Feb 22, 2026

The role of government and the community has changed significantly over the last two decades in relation to environment protection, particularly in the mining sector. Increased community expectations have moved well ahead of regulatory requirements, and there is now a much greater appreciation generally of the concepts of ecologically sustainable development and intergenerational equity, and the gap between current practice and practices which would be in harmony with these concepts. Besides providing a `safety net' through regulations to ensure that basic environmental performance standards are met, government is now working proactively with the mining industry to encourage higher levels of environmental performance. This paper describes some initiatives between the Commonwealth government and the industry designed to achieve these higher levels of environmental performance, through programs aimed at the paradigms of best practice environmental management and continual improvement.

Jan 1, 1997