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By John W. Straton

Following the completion of the paper presented in February, 1972, data were received from many other mines and some original respondents submitted more complete questionnaires. The computer program was changed to permit the results to reflect more clearly all the data reported by the mines. The original paper was revised to reflect the new information. There were significant changes in some numerical values, particularly where the size of the sample changed appreciably. Some limited samples considered originally in arriving at conclusions were not relied on in this revision. The revised tables and text are of the same design and format as the original paper.

Jan 1, 1972

By John A. Riddle

Some of the pitfalls and problems in selecting and applying corrosion-resistant materials in uranium plants are discussed, together with some suggested solutions. Includes some cost data.

Jan 1, 1979

By David Jurich, Ed Perko, Jacob Prezkuta

Numerous Colorado mountain tunnels that date to the late 1800s convey water to the farming and urban communities of the eastern Front Range. Repairs to these remote facilities, often located in public lands at altitudes of 11,000 feet or more, require detailed planning, close coordination with multiple agencies, and creative execution. Issues and solutions discussed include designing repairs in undocumented ground and support conditions, logistical challenges, work in a short summer construction window, stabilization of historically signicant structures, and proect delivery strategies. xamples that illustrate early contractor involvement, exibility in design, and construction solutions are presented.

Jun 23, 2024

By Larry Cook

During the past year the news media has come in for its share of criticism. Some of it, without doubt, is justified. Much of it, like that which has been leveled against some of the rest of us, is not. We can sympathize with the newspapers and magazines, the radio and television stations. Like the coal industry, which I represent, they are a part of the free enterprise system. They depend upon advertising for their existence, and advertisers patronize those media which reach the most people interested in their product. The various news media are therefore In avid competition for circulation. Although they do have an unquestioned influence on the public, they are primarily a reflection of the public and it is in this context that we will consider them. Granted that this reflection is sometimes a bit distorted, let us admit that any subject which does not strike a responsive chord In the public will soon be dropped by the media.

Jan 1, 1970

By W. Clark Ashby

Productivity is a fascinating concept. Like motherhood or apple pie, we know it as a good thing. Just what it means is not so clear. To a coal miner we assume it means tons of coal hauled from the mine. To the company president it means profit after capital, labor, and other costs have also been reckoned. To the government economist it means output in a balance of payments. What does it mean to the biologist, and can reclamation really be productive? In this paper we discuss productivity from a biological viewpoint, give some yield data for various types of reclamation plantings, and discuss how our demand for or acceptance of differing kinds of productivity is tied up in bigger questions of land use, environmental stability, and resource allocation.

Jan 1, 1981

By Christian F. Baiz

The author will present a discussion of the steps which must be taken by the prospective developer of a small mining operation to establish technical credibility when seeking financial backing. Particular emphasis will be given to the differing levels of technical work (and their relative cost) which must be accomplished to supply the information necessary to satisfy potential investor groups, whether they be other mining companies, equity investors, or financial institutions such as venture capital firms or commercial banks.

Jan 1, 1981

By Ing. E. h. Martin Herrenknecht, Werner Burger

In recent years, there has been a dramatic increase in the number of machine driven soft ground tunnelling projects. This increase is largely due to the technological development of slurry and EPB Shield systems. A new generation of soft ground tunnelling machines, markedly different from those of five years ago, now overcomes ground conditions that until now were too costly and impractical to undertake. The paper reviews the latest soft ground tunnelling machine developments in material transport, guidance and control, seismic surveying, soil conditioning, settlement control, cutting tool applications and variable mode operating systems. Specific projects where this technology has been applied will be highlighted.

Jan 1, 1999

By P. I. Prescott

Ground calcium carbonate (GCC) is used in the paper, plastics, paint, rubber, caulks, and sealants industries. The favorable properties of GCC include high whiteness and brightness, low hardness, and outstanding rheology in water systems. The quality of calcitic GCC ores, which include chalk, limestone, and marble, is dependent on calcite purity and the nature and quantity of ancillary minerals. Wet and dry grinding is used in the manufacture of GCC. Ore processed by optical sorting, flotation, and/or particle size classification has higher brightness and lower abrasion. GCC markets are a function of the product's properties, purity, and cost.

Jan 1, 1995

By John J. Sammarco, Alan G. Mayton, Elaine N. Rubinstein

Researchers from the National Institute for Occupational Safety and Health (NIOSH) developed a light-emitting diode (LED) area luminaire called the Saturn and conducted a laboratory study using a Fletcher High Dual-boom Mast Feed (HDDR) roof bolting machine. The Saturn luminaire was designed to (1) enhance floor illumination to enable better detection of trip hazards in the interior spaces of a roof bolter and (2) reduce glare that has typically been an issue of concern on roof bolters. This paper reports on the results of achieving the second objective. The existing roof bolter lighting was the baseline and was compared with three versions of the Saturn luminaire relative to light intensity (100%, 75%, and 50%). Discomfort and disability glare data were obtained from 30 participants that comprised three age groups. Discomfort glare perceptions were obtained using the De Boer rating scale, and disability glare was quantified by using Mars Letter Contrast Sensitivity tests. Discomfort glare was reduced at least 3 levels with all Saturn versions. Also, a predictive model was used to estimate discomfort glare, and the results were similar. Disability glare was the least for the Saturn’s 50% intensity, and all Saturn versions had significantly less disability glare than with the baseline lighting. Veiling luminance was calculated and used as another indicator of disability glare. Veiling luminance was 28 to 42 times greater with the baseline lighting as compared with that of the Saturn lighting. Lastly, visibility levels were calculated. The Saturn versions were 4 to 6.5 times better in terms of visibility level.

By Darrell V. B. . McClarty

In 1996, Rio Algom, Denison Mines and the Elliot Lake Research Field Station (ELRFS) formed a consortium to implement a regional environmental information management system (REIMS) for the Elliot Lake area in Ontario, Canada. ELRFS is an affiliate of Laurentian University in Sudbury, Ontario, The discovery of uranium in the Elliot Lake region in post-World War II led to the development of 12 mines and 11 associated mills between 1955 and 1958. During the late 1980s, declining world demand for uranium, combined with the discovery of high-grade uranium ore in other areas of the world, made the Elliot Lake mines uneconomical. As a result, all area mines ceased opera¬tions by the end of 1996. The eight facilities and three tailings management areas operated by Denison Mines and Rio Algom's five mining waste management areas contain 150 Mt (165 million st) of potentially acid-generating tailings. The areas cover 13.2 km2 (3,265 acres) and receive drainage from an additional 13 km2 (3,212 acres). The primary objective of the joint initiative was to implement a personal-computer-based, regional, environmental-information management system for managing historical data and ongoing environmental programs in the Elliot Lake region. The Elliot Lake consortium decided it needed an information system with an integrated, process-oriented and requirements-driven approach to collect and manage the environmental information. Following a study of environmental information management systems currently used by the mining industry, the consortium decided to base REIMS on the "Envista" product. This is a commercially available, environmental information management system marketed by Envista Technologies of Saskatoon, Canada.

Jan 1, 1999

By Ali Ahmadi, Andreas Rausch, Angela Binder, Stefan von der Mark, Dhananjeyan Jeyaraj, Jana Thomas, Nils Nöther, Stefan Wittek, Thomas Ulrich, Eleni Gerolymatou, Mario Kolling, Helmut Mischo, Michael D. Martin, Tugba Sen, Jens-André Paffenholz, Erik Farys, Oliver Langefeld, Wilfried Ließmann

This paper outlines the MOVIE project, which is dedicated to the development of a digital twin for an underground laboratory at the research and education mine “Forschungs- und Lehrbergwerk Reiche Zeche” in Freiberg (Germany). Data from induced rock deformations and temperature fluctuations is collected using fiber-optic sensors. The objective of the project is to establish a virtual laboratory for real-time analysis of the interactions between geology, geomechanics, geometry and ventilation. This will be achieved by integrating models from these disciplines with artificial intelligence, creating a sophisticated hybrid model. The insights gained will enhance safety and efficiency in mining through improved digital planning options, ultimately contributing to more effective resource management and operational decision-making in different mining environments.

Feb 1, 2025

By E. Ashworth

A thermistor probe has been developed to measure in situ temperature profiles underground. A full description of the probe is given. Data collected from the probe has been used to compare the actual profiles with those predicted from a finite element analysis using laboratory measured thermal properties of the different rock types. This comparison indicates the applicability of laboratory measured parameters in modeling the real conditions. Factors such as applied pressure, moisture content and anisotropy on laboratory measurements is discussed.

Jan 1, 1983

By R. W. Plume

Gold extraction along the Carlin trend requires large withdrawals of ground water, which can be perched, unconfined at shallow depth, and (or) confined at depth. Five hydrogeologic units-Quaternary basin-fill sediments, Tertiary basin-fill sediments and sedimentary rocks, Tertiary volcanic rocks, Devonian to Ordovician siltstones, and Devonian to Ordovician carbonate rocks--form the framework for two aquifer systems that discharge along some reaches of the Humboldt River and its tributaries and are recharged by streamflow along other reaches. Ground-water withdrawals eventually could affect these stream-aquifer interactions. Further work is needed to quantify regional hydrologic processes and evaluate potential effects of mining on water resources.

Jan 1, 1992

By Brian Fulcher, Matthew Bartlett, Jarrett E. Carlson

This paper discusses the challenges to complete the construction of two large underground Metro stations and connecting tunnels in the Tren Urbano system. The completion work includes the installation of specialized mechanical and electrical systems, extensive architectural finishing as well as coordination with systemwide power and controls installed by others. A unique feature of this project was the simultaneous design and construction of the structural/civil/architectural/mechanical/electrical works by KKZ separately from the power and control systems under the management of the Owner, its consultants and other contractors. Completion of this project comes after almost six years of continuous design and construction in a dense urban environment. The project was confronted by many challenges that could only be met with the combined efforts of the Joint Venture team in close cooperation with the Owner and its System wide Contractor. This paper will also address many of the major design and construction changes implemented to suit the Owner’s requirements.

Jan 1, 2003

By Chris McKee

Quartz has been of interest in occupational health for years because it can cause silicosis after prolonged exposure. New OSHA regulations (Air Contaminant; Final Rule) list perlite as a nuisance dust. They conclude that perlite is nontoxic when air-borne total particulate concentrations are 15 mg/m3 or below and when quartz content is less than 1% crystalline silica. OSHA has established an 8-hour PEL of 15 mg/m TWA for total perlite dust containing less than 1% quartz. OSHA has established a 5 mg/m3 TWA PEL for respirable perlite. These limits will protect workers from significant risk of eye, skin, or other physical irritation. This regulation is based on a Group 2A classification as a probable carcinogen in humans, at the 0.1% crystalline silica level, by the International Agency for Research on Cancer (IARC 1987a, b). IARC found sufficient evidence for carcinogenicity of crystalline silica in animals and limited evidence in humans. Perlite is not listed as a carcinogen by OSHA or the National Toxicology Program.

Jan 1, 1990

By Steve Kral

The third edition of the Underground Construction Association of SME?s (UCA) Cut-ting Edge series of conferences focused on a challenge every underground construction and tunneling project faces: controlling ground water. The conference, held in New York City in November, is a partnership between the UCA and The North American Tunneling Journal. It featured more than 20 technical presentations by professionals from around the world. Each described specific challenges unique to their projects and the solutions employed. More than 175 professionals attended the two-day conference that included an exhibition featuring 17 companies. In addition to the technical program, the Cutting Edge conference featured a site visit to the $10.4 billion East Side Access Project. Sponsors of the meeting included Soil Freeze, Traylor Bros., Kiewit, Skanska, Moretrench, Aecom and The Robbins Co.

By R. V. Ramani, K. V. Raj, S. Bandopadhyay

The air flow problems in openpit mines are complex. Computational fluid dynamics (CFD) models can provide detailed information regarding air flow pattern, velocity distribution, temperature, and pollutant concentration in an enclosed domain of an openpit mine. A range of turbulent models can be selected with varying complexity and accuracy. Pollutant transport models, however, differ in their assumptions and structure as well as in the algorithms they use. As a result, predictions vary from model to model. This paper presents a study of pollutant transport in an actual openpit mine under a stable boundary layer. The objective was to test two turbulence models using similar geometry and the same input conditions and model constants. Measured data were used to compare the results of the two CFD models, namely, the kappa-epsilon (к-є) model and the Large Eddy Simulation model. Despite the complex synoptic situations, different meteorological input data and fast-changing conditions, the simulation results from both the models were in good agreement regarding the dispersion of pollutants.

Jan 1, 2015

By Charles W. Bauer

Most of the aluminum produced in the United States today is derived from foreign bauxite deposits. Earth Sciences, Inc. initiated a program to evaluate domestic non-bauxite sources for alumina in the 1960's. In the initial evaluation of alunite, domestic resources were not sufficient to support development. An exploration program led to the discovery of large deposits of alunite in Utah and several other western states. Identification of alunite is difficult as both its physical and chemical characteristics are similar to the minerals with which it is associated. Most of the significant alunite deposits in the western United States are replacement type deposits. These deposits have formed as a result of hydrothermal alteration of volcanic, sub-volcanic, and igneous rocks. Typical alunite deposits contain between 30% and 50% alunite between 50% and 70% quartz with minor amounts of other minerals. Four mineralogical zones are common in these systems. They include a siliceous zone, a quartz-alunite zone, a kaolinite zone and a chlorite-montmorillonite zone. Total U.S. reserves of alunite were estimated at 20 million metric tons (at 30% alunite) by the U.S. Bureau of Mines in 1941. Here recent work by the U.S. Geological Survey estimates reserves of 252 million metric tons and potential resources at 1.4 billion metric tons. Reserves and resources estimated for 23 properties on which field work has been done by ESI are considerably higher. Most of these properties have reserves and potential resources of several hundred million metric tons. The combined demonstrated reserves at these properties are estimated to be about 650 million metric tons. Inferred reserves are estimated at 2.5 billion metric tons and potential resources at 8 billion metric tons. It appears that the U.S. has sufficient reserves and resources for alunite to be considered as a potential non-bauxite source of alumina.

Jan 1, 1980

By W. M. Luff

Introduction The Brunswick No. 12 mine is located about 27 km (17 miles) southwest of Bathurst, New Brunswick. The deposit is a stratiform massive sulfide deposit occurring in a series of sedimentary and volcanic rocks of the Tetagouche Group. These rocks are generally considered to be Ordovician in age. Ore reserves at Brunswick No. 12 are 104 Mt (115 million st) grading 3.72% lead (Pb), 9.01% zinc (Zn), 0.32% copper (Cu), and 97.9 g/t (2.8 oz per st) silver (Ag). Production in 1984 was 3.5 Mt (4 million st) at 3.57% Pb, 8.91% Zn, 0.32% Cu, and 100 g/t (2.9 oz per st) Ag. Total payable silver production that year was 211 t (6.8 million oz). This made Brunswick one of the largest silver producers in Canada. Bathurst-Newcastle area and Brunswick Mining Interest in the Bathurst area was aroused in 1897 when W. Hussey discovered an iron formation at Austin Brook, just south of Brunswick No. 6 deposit. This area, and the current No. 6 area, was explored from 1897 to 1907. Iron ore was mined at Austin Brook from 1907 to 1913 and from 1942 to 1943. Any occurrence of sulfides was overlooked until 1952. In 1952, M. J. Boylen Enterprises investigated the small sulfide body associated with the Austin Brook iron formation. Other electromagnetic anomalies associated with the iron formation were investigated. The No. 6 deposit was found late in 1952, when hole B12 intersected 97.5 m (320 ft) of massive sulfides. The No. 12 deposit, 10 km (6 miles) to the north, was found in 1953. More than 30 massive sulfide deposits have since been identified in the Bathrust area. In the 1950s, St. Joe Lead Co. did extensive test work on the No. 6 and No. 12 deposits, including shafts at No. 12, lateral development at No. 12, and testing at both deposits.

Jan 10, 1986

By Cliff Holloway

The past year has been difficult for Canada's primary industries. The mining, oil and forestry industries have been hit by low prices and a reduced demand for natural resources. Foreign competition, militant environmentalists, the breakdown of the Asian and European economies and Canada's shrinking dollar have all put additional pressures on the commodity purchaser to buy smarter. It is easy to appreciate why operations and maintenance supervisors want the best performing product. It makes good sense. The challenge is to source that quality product while staying within the budget. The bottom line (price), however, often becomes the control- ling factor, usually at the expense of quality and performance. This is short-term thinking, often with expensive consequences.

Jan 1, 1999