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By B. R. Conard

Occupational epidemiology of the nickel-producing industry has found that inhalation exposures to certain nickel-containing substances are linked to respiratory cancers and to nonmalignant respiratory endpoints. Establishing such a linkage, however, is complicated by the fact that some diseases occur long after exposure to a causal agent (i.e., some diseases have long latencies). Furthermore, most chemical agents (especially nickel substances) vary significantly in their toxicological properties and their concentrations in workplace air have varied over processing history. Because of these complications, it is critical to understand historical exposures to specific nickel substances. To assist in this effort, the author focuses on the history of smelting and its related processes at Vale Canada’s (Inco’s) Ontario operations in the first half of the 20th century.

Jan 1, 2012

By W. K. Tolley

The Bureau of Mines is testing super critical fluids as solvents to selectively extract valuable components from complex matrices. Materials recovered during supercritical fluid extraction are often highly purified. Using laboratory apparatus designed specifically for supercritical fluid research, Bureau re-searchers have measured the solubility of titanium tetrachloride (TiCI4) in supercritical, liquid, and gaseous carbon dioxide (C02), CO2, a commonly used supercritical fluid, is inert, inexpensive, and nontoxic. Supercritical CO2 formed a single phase with TiCl4 at 45° C and 1,500 psig. When the solution was heated at constant pressure beyond 55° C, TiCl4 precipitated from the fluid. Results showed that TiCl4 solubility in supercritical CO2 is not controlled by the vapor pressure of the solute.

Jan 1, 1989

In 2006, a total of 280 metal mining operations reported employment to the Mine Safety and Health Administration (MSHA).1 Metal mines were the smallest mining commodity sector, comprising 1.9% of all mining operations. ? Gold mines comprised 46.8% (n=131) of all metal mining operations. Other common types of metal mines were copper ore (n=34; 12.1%), and iron ore (n=33; 11.8%). Nevada had the largest number of metal mines (n=53; 18.9%), followed by Alaska (n=31; 11.1%).

Sep 1, 2008

By Collin Stewart

Bowie Resources, LLC (Bowie) has been using the Stability Mapping System (SMS) developed by Dr. Keith Heasley, West Virginia University, since 2005. Seven three-entry longwall gateroads, four longwall panels and a five-entry set of mains have been mined in two different seams in areas originally analyzed with the SMS. This paper compares predictions of mining conditions based on the SMS with actual mining conditions. Specific comparisons include longwall and continuous miner (CM) productivity, longwall tailgate response and support and CM roof bolting requirements. The paper also discusses current thoughts at Bowie on the use of different weighting factors for CM development, longwall face conditions and longwall tailgate support requirements.

Jan 1, 2007

By T. H. Dubaniewicz

Many mines rely on toxic gas sensors to help maintain a safe and healthy work environment. This report describes a prototype monitoring system developed by the U.S. Bureau of Mines (USBM) that uses light to power and communicate with several remote toxic gas sensors. The design is based on state-of-the-art optical-to-electrical power converters, solid-state diode lasers, and fiber optics. This design overcomes several problems associated with conventional wire-based systems by providing complete electrical isolation between the remote sensors and the central monitor. The prototype performed well during a 2-week field trial in the USBM Pittsburgh Research Center Safety Research Coal Mine.

Jan 1, 1995

By Jürg Künzle

Underground construction is a matter of dealing with the inherent uncertainty of subsurface geology. If the encountered conditions are less favorable than the expected ones, the execution of excavation, support, ground treatment or lining works is likely to require more or different efforts than anticipated, thereby delaying the works and increasing the costs. The 2019 first edition of the FIDIC Emerald Book model contract (FEB) addresses many of the issues to which underground works give rise, including those related to differing site conditions (DSC). This paper examines how under the FEB disputes arising from or in connection with DSC could or should be avoided.

Jun 13, 2021

By Robert J. Timko

In early June 1986, an underground fire of unknown origin erupted in one of several entries of a coal mine located in southwestern Colorado. For a time, mine personnel aggressively fought the fire. However, control of the fire was later lost. To prevent further damage and reduce the possibility of an explosion, all portals and shafts to the mine were sealed. The mine operator requested the U.S. Bureau of Mines' assistance in obtaining and analyzing mine fire gases taken from sampling ports placed through the mine seals, as well as down boreholes drilled after the fire. This report recounts activities within the first 2 years of the mine being sealed. It includes a description of gases analyzed and mine atmosphere status equations generated from the analyzed gases. The gases were analyzed by chromatography and included standard atmospheric gases as well as higher hydrocarbons that are found in postfire atmospheres. Nine equations were used to evaluate what was occurring within the sealed mine. Following a description of the rationale behind each equation, the 2-year trend is briefly analyzed.

Jan 1, 2010

By Barton, Donald C.

THE elastic, earthwaves produced naturally by earthquakes -have been used for a long time as evidence from' which to draw conclusions in regard to the constitution of the interior and crust of the earth. The elastic earthwaves produced artificially by occasional explosions and recorded by seismological .observatories were used to draw conclusions regarding the-geology of the intervening area. Intentionally produced elastic earthwaves in the past five years have come to be used extensively in the investigation of very local geologic structure. The seismic method of working geologic structure, which makes use of artificially controlled explosions and the resulting earthwaves, has developed almost `clairvoyant power in handling certain geologic situations, and in the discovery of salt domes in the Gulf Coastal: Plain region of Texas and Louisiana has 'scored the, most brilliant success.

Sep 1, 1928

By Paul Eimon

The 1981 Fall field trip of the Denver Region Exploration Geologists' Society focuses on Creede. That is appropriate - because significant mining history has been made and is being made in this off-the-beaten track, high-country mining district. Creede is one of the few Colorado bonanza towns which was big in the 19th Century, had its ups and downs, and produced almost continuously since its discovery. Creede is important to geologists for its: precious and base metal production, current exploration activity, and research into near-surface hydrothermal systems. United States Geological Survey research and field geologists zeroed in on Creede some 25 years ago and their steady, consistent work is now being spotlighted and appreciated.

Jan 1, 1981

By C. N. Speltz

The cost of transportation of industrial minerals is frequently higher than the cost of the product. Where a minc, industrial mineral plant. or customer is served by a single railroad, that single railroad, because of lack of competition, may increase rates and/or provide inadequate service so that the economics of that mine, plant or customer are adversely affected, or so that the level of service precludes satisfactory performance. Transloading of industrial minerals from rail-to-truck or truck-to-rail in order to improve economics and sales of product is not new. However, transloading to reduce freight costs or improve inadequate service caused by a lack of competition in the rail industry, is a relatively new concept brought on by the recent mergers of many of the main line railroads, both in the eastern and western United States. For example, with completion of the Burlington Northern/Santa Fe and the Union Pacific/Southern Pacific mergers, the western United States has only two mainline railroads. The industrial mineral producer, in order to reduce the cost of transportation, or increase the level of service, must evaluate potential transloading opportunities in light of higher prices and reduced service brought on by reduced railroad competition.

Jan 1, 1998

By J. B. Janus

This report, the 22d in a series, gives analytical data showing composition and quality of tipple and delivered samples of coal collected during fiscal year 1972. This coverage lists mines located in 20 States. Ultimate analyses are given for most of the coalbeds listed. Tipple samples were collected by Bureau of Mines engineers at tipples as coal was being loaded into railroad cars or trucks. The deliveries were sampled in accordance with instructions issued by the Bureau of Mines, and the samples were analyzed in the Bureau laboratory at Pittsburgh.

Jan 1, 1973

By A. J. Kraemer

This report on the physical and chemical properties of crude oils of California is one of a series on the producing districts of the United States. It includes a short discussion of results, tabulated data, and individual analyses of California crudes. Analyses of crude oils from the fields of Fresno, Kern, Los Angeles, Orange, and Ventura Counties have been published in Serials 25952 and 26083. The analyses reported in this paper corer samples that were obtained subsequent to the publication of Serials 2535 and 2608. The samples were obtained by members of the San Francisco office of the Bureau of Mines. The collecting of samples was facilitated by the courtesy of representatives of oil companies in California.

Jan 1, 1927

By Norman A. M Macleod

FOR the past seven years, all flotation at the Britannia mill has been done in Forrester Air-Lift cells. Prior to 1931, the roughing and part of the cleaning operation had been performed in four 21-cell and two 14-cell M.S. machines. The resulting economies in reagent, power, maintenance, and general operating costs, and the increased recovery, more than justified the exclusive use of the Forrester machine. About three years ago, the possibility of still further improving the efficiency of the flotation section was the subject of considerable discussion and experiment. Arising from these experiments, tests were made of the practicability of using a cell of greater depth than that of any pneumatic or mechanically-agitated machine in common use. Cells were constructed with depths of 7 .5 feet, 10 feet, and 15 feet, and, in all cases, a very definite improvement in operation was indicated. The cell now being used in the mill treats from 5,500 to 6,200 tons of dry feed per day. It is 100 ft. long by 5 ft. wide by 8 ft. deep, and has replaced a total length of over 500 feet of standard Forrester machine. The choice of a depth of 8 feet was governed by the type of blower which was available-in this case, a Roots-Connersville blower, driven by a synchronous motor and delivering 6,000 c.f.m. of free air at 4.0 pounds per square inch. At the Chelan Division of the Howe Sound Company, where a new mill was recently built, all flotation is carried on in cells 10 feet deep, with good results.

Jan 1, 1938

By R. D. Pehlke

The history and present status of continuous casting of steel are reviewed, including a genera 1 description of current processes. Plant layout, process development and elements of machine component design are outlined, and key steps in integration into a stee-1 production system are detailed. Recent productivity advances and improvements in quality are described. Process developments are reviewed, and some future avenues for this technology are considered.

Jan 1, 1985

By The Staff

THE property of McKenzie Red Lake Gold Mines, Limited, consists of eleven claims located on McKenzie island in Red lake. The mine is about 4,Y:l miles by water from the Howey townsite on the same lake, and about 95 miles north of Kenora, Ont. (see Figure 4). Mail and express are flown-in daily, winter and summer, from Sioux Lookout, Hudson, Kenora, and Winnipeg. All heavy supplies are freighted-in during the summer over a water route, using four marine railway portages, from Hudson, Ont., a distance of about 180 miles. During the winter, freighting over the same route is clone by tractor if necessary, but costs are three to four rimes the summer rate. Due to these conditions, large inventories of supplies must be kept on hand, varying from a spring minimum of $45,000 to a peak of $110,000 early in November. The average cost of all freight brought in from steel during 1937 was $0.01 per pound.

Jan 1, 1938

By Alexander Darío Huamán Ccorahua, Cayo Fernando Soto Buendía, Jhonatan Raphael Rojas Ventura

Lithium is a top-quality mineral in the energy market, with growing demand. It has many applications in medical, nuclear, and energy industries. The purpose of this article is to quantify and analyze the economic potential and projected global demand for lithium annually. It aims to determine Peru’s (specifically Puno) positioning in the global context in 2025 and 2030. The article also seeks to identify the main regulatory, environmental, and social challenges to sustainably exploit lithium in Peru. The study employs applied research (mixed approach), descriptive-correlational scope, and observational, crosssectional design. The methodology demonstrates the use of statistical techniques to model and make predictions about this energy-transition metal. Academic sources were reviewed to enable a comparative approach and projection into the future of lithium for development in the mining industry. In the last 10 years, lithium demand has grown, noting a 600% increase in the economy and projected annual growth of +26%. Exponential growth in resources is projected, where econometric, R-multivariable and R-linear models estimate that Peru could supply 1.5% in 2025 and 3% in 2030 of global lithium. Estimated growth of 5–15% in socio-environmental conflicts is projected with the start of lithium exploitation (Peru – Puno). The global potential of lithium demonstrates exponential growth. Lithium reserves in Puno - Peru would rank 13th between 2025 and 2030. It is necessary to establish a clear regulatory framework to avoid excessive increase in socio-environmental conflicts.

Feb 1, 2024

A mining operation can be identified as demonstrating prudent management when a number of vital characteristics are evident.All risks and opportunities that are critical to the on-going success of the operation have been identified and are being effectively managed. All significant tasks and events are plan driven. All levels of management visibly support the policies of the operation through their attitude, behaviour and actions as well as words. Supporting evidence for required activity and the outcomes is readily available. Improvement mechanisms are working to advance the key business processes. Everyone is working towards satisfying the needs of the stakeholders of the operation. When these characteristics are integrated with the satisfaction of all legislative requirements, all industry codes and optionally all relevant international management system standards then an operation is fulfilling all the requirements of a Due Diligence Process. The majority of mining operations do not show all of these characteristics and therefore unnecessarily suffer from missed profit opportunity and constant cost pressure, less than acceptable safety and health and environmental performance and consequent poor relations with employees, unions and regulators. In these operations the characteristics to be observed are quite different.Serious incidents are occurring with no sign of a rate decrease. The operation lurches from one panic ituation to another. Management are absent in their leadership, but very active in developing rules and enforcement methodologies. The operation has no history. Re-inventing the wheel with employees who come and go at an alarming rate seems to be forever occurring. All efforts are directed at controlling the business outputs with a strong emphasis on blame. Everyone is trying to look busy to avoid the ever-present cost reduction threats. To change to more prudent management utilising a Due Diligence Process is not theoretically difficult. However it does take clear direction, focussed efforts, supporting actions with appropriate tools and perhaps most importantly an internal desire and drive to become such an operation. A Due Diligence Process is about doing the important things that have to be done, providing the understanding of why they are important, demonstrating proof of activity and effectiveness, and leading the way through effective management.

Jan 1, 1998

By G. Belardi

The purpose of the study was to check on the level of environmental contamination and to design a project for cleaning up the Abetina Mine area at Piancastagnaio (Grosseto, Italy). Contamination of this area had occurred during the mining and treatment of cinnabar (HgS) over a prolonged period. The aim of the project is to remove the sources of contamination or render them harmless. Mining of the Piancastagnaio deposit started in 1840, mercury metal being extracted from the ore by thermal treatment. Together with Spain, Italy was the first country to produce this metal and was the world leader in this field between 1936 and 1943. Though mercury production in the Monte Amiata region of Tuscany ceased in 1974 the ensuing environmental impact is very evident, taking the form of rusty old mining and processing works, plus waste tips which still contain considerable amount of mercury even after the ore had been subject to thermal extraction treatment. The research which has been conducted included mapping the area to identify the main sources of mercury and arsenic pollution, as well as the level of environmental contamination. Mercury and arsenic values in excess of 16,000 and 150 ppm respectively are encountered in the most highly-contaminated places. The cleanup project has been drawn up on the basis of the field and laboratory investigations. This provides for a combination of remediation measures on the land concerned, as well as in situ inertization of contaminating elements by means of mixtures of chemical compounds such as cyclosiloxanes. Due account has been taken of Italian and EU environmental regulations when establishing the measures for rendering the various polluting element innocuous. 'The efficacy of the inertization techniques has been checked by yield tests in acetic acid and carbon dioxide, reducing the Hg and As contents of the material in the untreated and treated states from maximum values of 7 mgll to minima close to zero.

Jan 1, 1996

By T. A. Simpson

The search for ore continued at its relentless pace throughout 1967. Canada, South Africa and Australia plus a few scattered localities on the globe reported minerals finds of significant importance. Many of the reported finds were not high grade ore, but they nonetheless will assist in sup- plying a highly industrialized, mineral hungry world. No longer does inaccessibility and remoteness close an area to mineral exploration and development. The communication and transportation systems of today have closed the gap and, moreover, the demand for essential mineral commodities is causing price shifts which encourage exploitation of deposits heretofore considered uneconomical.

Jan 2, 1968

By J. H. White

It is hypothesized that the Hotelling Valuation Principle (HVP) can determine the value of developed gold reserves using simple methods and easily obtained data. This paper reports the results of an empirical test of this hypothesis. Using publicly available data from North American gold companies, we obtained data for V, R, p, and c and ran a simple linear regression using equation (1.1) as the definition of the dependent and explanatory variables. By examining the value of the coefficients of the resulting regression equation, we can draw conclusion as to whether or not the HVP can be confident1y used as an estimator of the value of developed gold reserves.

Jan 1, 1995