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By Gary S. Brierley, Ronald E. Romley, Alan L. Howard

The Price Road Drain Tunnel in Tempe, Arizona is part of the drainage system constructed in conjunction with the Outer Loop Highway in metropolitan Phoenix. The Outer Loop Project is a part of a much larger expressway system that includes other large drainage tunnels such as the Papago Freeway Drain Tunnels. Large diameter downhole inspection borings were utilized to obtain subsurface data for the design of these tunnels. Subsurface data obtained from the large diameter borings resulted in the development of empirical parameters that were successfully incorporated into the Geotechnical Design Summary Report and which satisfactorily predicted ground behavior, formed the basis for improved geotechnical design criteria, and facilitated the cost effective assessment of third party risk. The purpose of this paper is to describe the subsurface exploration program performed for this project and to explain the methods used to evaluate underground construction procedures.

Jan 1, 1991

By Richard Keith Corbin

Canadian junior mining companies whose gold exploration and exploitation programs take them across the border into the western United States should be prepared to deal with the myriad of title issues involved in acquiring unpatented gold mining claims. The purpose of this paper is to serve as an introductory outline for Canadian junior mining companies to mining laws of the United States, as well as to relevant laws of some of the western gold mining states. Topics will include the five w's (who, where, what, why and when) of Canadian junior mining companies1 rights and responsibilities in acquiring interests in U.S. gold mining properties by claim staking, lease or purchase. Historic terms of common parlance among U.S. miners, such as "claimjumping" are defined and discussed. Various legal doctrines, such as "pedis possessio" and "good faith" in the location of claims are covered as well. Controversial subjects of contemporary interest are addressed in some detail, such as whether to locate a bulk-mineable disseminated gold deposit with placer claims or lode claims, and whether lodes may be staked over placers. By thus heightening the awareness of Canadian junior mining companies, it is hoped that they can be properly prepared to avoid title disputes, and to win lawsuits when they are unavoidable.

Jan 1, 1988

By Otis M. Clarke

The Eufaula bauxite-kaolin district in southeastern Alabama is an important source of raw material for the refractory industries in the United States. At the present time, five companies are mining and processing bauxite and kaolin from this district and a sixth company is holding substantial reserves. Mining operations are expanding, but finding new ore reserves is a major problem. The Geological Survey of Alabama sponsored geologic research in the Eufaula district to: 1) investigate the utilization of sandy kaolinS and other clays associated with bauxite-kaolin deposits; 2) find limits of the bauxite district, looking for possible extensions; and 3) study the geology of the district, looking for patterns or trends that may aid in finding new ore reserves. This work was done with the full cooperation of mining companies operating in the district and property owners. Research was aided by the U.S. Bureau of Mines and the University of Alabama. The investigation included detailed geologic mapping of mines, drilling in selected areas, and making mineral analyses of bauxite and clays. The mapping was performed primarily by pace and compass because of the complexity of the deposits studied, but aerial photographs were used to a limited extent. Drilling included both auger and core drilling. The auger drilling was limited to 100 feet, but core holes were drilled as deep as 200 feet. The term 'bauxite,' as used here, indicates a mixture of minerals containing more than 50 percent gibbsite. Bauxitic clay is a mixture of gibbsite and kaolinite that contains more kaolinite than gibbsite. The term "kaolin" indicates a clay composed of predominantly kaolinite. Other clays in the Eufaula district are composed of kaolinite, illite, quartz, mica, and goethite or hematite.

Jan 1, 1971

By D. H. Davidson

In situ leaching (ISL) of copper has the potential of reducing both capital and operating costs for copper production. The ISL process combines surface facility (SX/EW) and wellfield operations, each of which must process the same total flow rate and pregnant liquor copper concentration. Commercial cost data are only available for SX/EW facilities. This paper discusses: the interaction between the principal wellfield costs associated with well modules, and wellfield start?up with SX/EW costs; how to estimate what the level of wellfield costs must be to optimize DCF/ROR; and how to relate these wellfield costs to orebody geologic and mineralogic characteristics.

Jan 1, 1988

By P. L. Webster, S. D. Thompson

The Coal Mine Belt Capacity Simulator (CMBCS) was originally developed to provide an improved belt capacity simulation through more detailed, flexible and realistic modeling of belt loading. While this model offered improved capacity design for conveyor belts and surge bins, it lacked the capability to simulate some key protection and segregation applications for bunkers. Recently, CMBCS was extended so that these latter bunker applications could be considered. In addition, a fear minor extensions were made to improve the model's flexibility and of efficiency. These various extensions and the steps taken to verify and validate them are described. The associated modifications in the model's input and output as well as the model's current requirements and availability are also discussed.

Jan 1, 1992

By Dennis V. D’Andrea, Peter G. Chamberlain, James J. Olson, William C. Larson

Blasts designed for in situ copper leaching must produce adequate fragmentation and permeability for successful leaching. Copper recovery depends to a large extent on the particle size distribution created by the blast, the permeability in the blast- fractured zone, and the ability to maintain solution flow with a minimum amount of channeling. This paper presents the results of Bureau of Mines experiments where core drilling was used before and after blasting to establish the degree of fragmentation. Data are presented from tests at the Sierrita mine of Duval Corp., and also from tests at the Emerald Isle mine of El Paso Mining and Milling Co. Copper recovery is predicted from fragment size distribution data using a computer model. Data from several blasts are used to show how predicted copper recovery is related to powder factor.

Jan 1, 1977

By J. G. Groppo, T. L. Robl, C. J. McCormick, W. M. Lewis

The combination of froth flotation and hydraulic classification can facilitate the production of a high-quality pozzolan that meets or exceeds ASTM specifications. This combination has been rigorously evaluated and results of pilot-scale testing are presented. Pilot-scale testing was conducted on fly ash from two active electric utility storage ponds. The tests demonstrated that a high-quality and consistent pozzolan could be produced using Advanced Pozzolan Technologies' Fast Float™ Process. Along with the pozzolan, the additional production of aggregate for masonry mortar and the production of a low sulfur, medium-Btu fuel were also demonstrated. The Fast Float™ Process incorporates several simple unit processes to ensure pozzolan consistency. Classification controls the particle size distribution, which is critical for achieving early strength;flotation controls the grade with respect to L.O.I.; and dewatering controls the moisture content.

Jan 1, 2000

By Richard D. Grove

The on-stream analysis of phosphorus and silica has not been possible by XRF techniques and only recently has some success been indicated with quantitative XRD for P. Yet there has been a recognized need for an on-stream analysis of P and acid insoluble to permit the automatic control of phosphate rock flotation plants which produce some 30-40 million tons of concentrate each year in the southeastern U.S. IMC Fertilizer, Inc., the largest U.S. phosphate rock producer, embarked on a program to develop such an on-stream analysis capability several years ago. Following many months of lab and prototype development, the first commercial installations started in December 1986 and now have completed some 400,000 analyses with surprising accuracy, precision and reliability. The use of these devices in the improved control of the phosphate flotation plant is currently receiving some very serious attention at IMC.

Jan 1, 1989

By Amy McBrayer, Vladislav Kecojevic, Juan David Valencia Quiceno, Dragan Bogunovic

The mining industry’s commitment to innovation reflects a history of adopting technological advancements to enhance workplace safety, environmental sustainability and vocational training. The objective of this research was to develop an augmented- reality (AR) system for heavy-equipment operators (HEOs) in surface mining. The developed system has the potential to enhance mine safety, training and data-driven decision- making, which presents a significant step toward a more sustainable, effective and technologically driven mining training, contributing to the industry’s evolution and growth. The AR training system leverages Microsoft’s Power Platform and HoloLens 2 capacities to provide operators with detailed and immersive training guides for three mining equipment, including bulldozers, motor graders and haul trucks. AR guides combine speech controls, 3D objects, informative images and explicative videos in the real working conditions to enhance the operator’s learning process. The system has the potential to modify the training structure based on user performance and provides an efficient approach to data collection during training. This project was developed and applied through a case study in a surface mine in the Southern United States.

Feb 1, 2025

By K. C. Kane, D. L. Meredith, B. E. Davis, D. A. Stanley, O&apos

Computer control of the minerals beneficiation process is limited by a lack of adequate sensors to provide information on the current state of the process. Recent reduction in the cost of image acquisition and powerful inexpensive computers make use of computer vision as sensory input in process control a possibility. In the phosphate industry, the amount of apatite in phosphate tailings is estimated by inspection. For machine vision, a simple 256 x 512 color image of the tailings was captured via an inexpensive color video camera on an IBM PC. Initially, the image is converted to gray scale and displayed on an EGA color monitor. A program was written which identifies the different constituents of the sample by analyzing the gray scale levels for the digitized picture. In other instances the minerals are identified by their relative color intensities. The amount of each constituent is determined with good accuracy from the area it occupies on the image.

Jan 1, 1990

By Jerzy Iskra, Wlodzimierz Sikora

INTRODUCTION The effect of stress concentration in coal seams leads to a sudden release in the form of rock bursts. This effect is controlled along many lines, but the most efficient methods consist in preventing the accumulation of energy in the seam or in the roof. The over- burden weight resulting from mining is the main cause of excessive stresses in a seam. An additional weighting of roof takes place due to formation of abutment loads. The accumulation of energy in the roof takes place where thick sandstone beds occur in overburden strata. An essential problem is to watch, with appropriate measurements, the stress of coal and roof rocks, and to conclude, on this basis, the degree of rock burst hazard. The methods for determining the stresses in a coal seam are quite well developed at present. Let me mention here the seismoacoustic methods, or borehole overcoring measurement methods. On the other hand, an examination of the state of stress in the roof rocks is almost impossible at the actual stage of development of the measuring technique. Hence, the model of stresses in roof was analyzed and determined theoretically. Based on this model, a technology for roof fracturing was developed which aims at destressing rock masses in a planned way. The essentials of the fracturing method consist of a controlled breaking of sandstone roof beds in order to: - prevent the excessive weight on the pillar - prevent a spontaneous breaking of roof beds at a limiting state followed by sudden energy release. High pressure fluid infusion is used to release buildup of stresses. THEORETICAL AND RESEARCH BASES According to the tests carried out by A. Kidybinski by the method of finite elements, isobars of stresses occurring in the roof over the working face are shown in [Fig. 1]. The results indicate: - the highest values of compressive stresses occur in the roof directly over the seam, at a distance of about 5 m ahead of the working face - at a distance of about 22 m above the seam there is a line of transition of compressive stresses into tensile - within the tested roof area, the highest tensile stresses occur at a vertical distance of 35 m, and at a horizontal distance of 20 m from the line of the working face. H. Gil (1) determined the pres- sure initiating the fracture of roof rocks by the formula: [ ] On the basis of results of analysis of isobars, and of the initiation of failure stress formula (1), isobars may be designed for a given roof class. Assuming for sandstones the Poisson ratio equal 0.3, a field of failure stresses presented in [Fig. 2] is obtained. In this figure it can be seen in which areas the effects of sandstone breakage may be obtained with the operation of a determined hydraulic pressure. To use formula (I), the knowledge of Rr is still necessary. This value may be determined in two ways: - taking a sample and testing it in the laboratory, if there is access to roof rocks in the existing openings, - drilling boreholes in the roof from surface and examination of the rock mass by using hydraulic breaking, if there is no access to roof rocks.

Jan 1, 1982

By Gregory Owen Lewis, Wendy Bouwer

Various processing strategies have been implemented in an effort to limit the loss of gold, during leaching, to the naturally-occurring carbonaceous 'preg-robbing' constituents present within certain gold bearing ore sources. Certain processing routes include complex and costly pre­treatment steps to reduce the negative effects of the preg­robber prior to dissolution, while others adopt a simpler direct leach/recovery approach. Process selection is largely dependent upon the gold deportment and the nature of the preg-robbing constituents within the particular ore. In the case of carbonaceous ores in which the bulk of the contained gold is available to direct cyanidation, carbon-in­leach (CIL) technology is generally applied with varying degrees of success. The effectiveness of the CIL route is governed by the competitiveness of the preg-robbing constituents in relation to activated carbon for the preferential adsorption of the solubilized gold. Trials have shown that the DOWEX MINIX strong-base gold-selective ion exchange resin has gold loading characteristics superior to those of activated carbon. The faster gold loading kinetics, together with the higher capacity of this resin, favour its use in an in-leach application as a more effective adsorbent for complex ores. This paper introduces the alternative resin-in-leach (RIL) technology, compares the metallurgical responses to RIL processing of different problematic ore sources, and discusses the interaction between various process conditions. Selected results from laboratory and pilot-scale testwork are presented to highlight the discussion.

Jan 1, 2000

By J. W. Mahar, E. J. Cording, F. L. Gau

INTRODUCTION The Washington, D.C. rapid transit system (METRO) when completed will consist of 98 miles of double track rail. Fifteen miles will be tunneled in rock and 12 large underground rock chambers will be constructed at station locations. The University of Illinois is under contract to Metro to provide observations and instrumentation services in the initial phase of construction. The work is coordinated through DeLeuw, Cather & Co., the General Engineering Consultant to Metro. The program is designed to monitor construction conditions as well as to provide information useful for the design of future rock tunnels and rock chambers in the Metro system. This paper presents the results of observations in the rock tunnels constructed to date. Most of the observations are in a 5000-ft-long, 30-ft-wide, double track tunnel in downtown Washington, D.C. Observations were also made in single track tunnels, shafts, enlargement areas, and pilot tunnels, and are being made in a large rock chamber 700 ft long, 76 ft wide, and constructed at shallow depth in a schistose gneiss. One of the major objectives of the observational program was to determine the orientation and character of joints and shear zones and to evaluate their effect on support requirements for various tunnel orientations and configurations. The consistency of geologic features throughout the Washington area has made the results of the initial study applicable to evaluation of support requirements on future tunnel contracts. The first section of this paper summarizes the geologic conditions in the tunnel and their effect on overbreak and rock movement.

Jan 1, 1997

By G. Papantonopoulos

Natural stones are extensively used for construction purposes since the dawn of human civilization, due to their unique aesthetical and technical characteristics. Their production and consumption has been continuously increasing over the past twenty years worldwide at an annual rate of 8.8%. European countries lead the race of per capita consumption, with Switzerland being in the first place with a consumption of 144.7 m2 per hundred inhabitants followed by Greece, Spain, Portugal, Belgium and Italy. On the other hand, during the period 2001-2002 the generated stone wastes were 110 million tones according to EU data, from which only about 5 million tones were recycled or re-used mainly in the construction industry. These stone wastes the non-natural wastes such as oils or chemicals coming from the equipment and machinery employed for stone extraction and processing, are disposed in the environment, posing serious environmental threat. To achieve sustainable development of the stone sector appropriate methods that will prevent or reduce waste generation and disposal have to be identified and applied. In this work an extensive study of the stone waste management techniques applied in Europe is carried out, in order to identify the Best Available Techniques (BAT) that can be used according to the type of generated wastes and the waste management hierarchy: Waste minimisation, Re-use, Recycling and Disposal. The identification of BAT was performed based on 14 Sustainable Development Indicators (SDI), which were grouped into three categories: environmental, economic and social. The developed final list of BAT includes waste minimisation techniques, eco-management schemes, in-situ treatment and appropriate storage and selection.

Jan 1, 2007

By James L. Vanderbeek

INTRODUCTION Semiautogenous (SAG) grinding technology first started to be seriously considered for comminution circuit design in the mid-1960s as an alternative to the three-stage crushing circuits and rod-ball mill circuits in vogue at the time. Since this time the application of SAG mill technology has become widespread with over 250 mills larger than 20 feet in diameter sold (Jones 2002). The vast majority of concentrators constructed over the past quarter century have utilized SAG mill technology, and a SAG-based comminution-based circuit is generally the first choice considered for new projects. Since the first generation of SAG milling technology was applied, many lessons have been learned, and new supporting technologies have emerged which make the design, installation and operation of SAG &-based grinding circuits more robust and efficient. This paper will discuss the current status of SAG and associated technologies. MILL MECHANICAL DESIGN ISSUES Table 1 summarizes the manner in which SAG design capability has evolved over the past 30 years. Increases in mill diameter came slowly as the industry took a wait-and-see attitude as the technology of larger mill diameters was advanced. The first 32-foot- diameter mill was ordered in 1969. It was not until 1979 that the technology jumped to the 34-foot-diameter mill and 1988 for the first 36-foot-diameter mill. The first 38- and 40-foot-diameter mills were both ordered in 1996. At least five 38-foot-diameter and two 40-foot-diameter mills will be in operation by mid-2004. Advances in structural analytical techniques and increased computational power, coupled with field measurements of large operating mills, have increased the confidence of the mill suppliers in their designs and the operating companies in the viability of larger diameter mills. No failures of a 36-foot-diameter mill or larger have been

Jan 1, 2004

By A. Ferreira Morgado, P. de Souza Santos

The sodium smectitic clays (bentonites), have more industrial applications in that class of mineral, a driving force to obtain this mineral. In Brazil, there are several occurrences of smectitic clays, unfortunately they are polycationic, with a distribution of several exchangeable cations, where the cation sodium occurs in minor quantity. In this work, the original polycationic smectitic clay was firstly proper characterized and then treated with sodium carbonate obtaining homoionic sodium smectitic clay. The rheological tests in the optimized sodium smectitic clay showed good results for drilling fluids, typical of a sodium bentonite ones.

Jan 1, 1999

By Stuart W. Maher

A major problem in future discoveries of base metals is their "explorability". By this I mean an exploration program must be designed that assures accurate assessment of the potential for ore, but is within reasonable budgetary constraints. As we are compelled to depend more and more on non-outcropping prospects, "blind" deposits, and as drilling costs multiply, the costs of exploration increase significantly. Solutions to the problem of defining exploration targets are influenced by our conceptions of the origin and recognition o f conditions that localize ore. The maxim that "elephants should be sought in elephant country" presumes we can recognize elephant country. This paper presents a suggested origin for some mineral deposits, and their controls; particularly those termed ?Mississippi Valley type". Tennessee is used as an example of the ideas offered. Mining districts designated "Mississippi Valley type" are, and have long been, the principal sources of barite, fluorite, lead and zinc ores in the United States and elsewhere throughout the world. A large volume of literature is available describing this class of ore deposits, explaining their habitat, and invoking genetic models for them. The quality of this literature is notably uneven, some of it demonstrably erroneous, and much of it is restricted to detailed descriptions of one aspect of the problem, or to detailed descriptions of one aspect of the problem, or to a single mine, or even a single stope. If an ore deposit is thought

Jan 1, 1977

By Nancy L. Jackson, Leslie C. Thompson

Acid rock drainage is one of the most complex issues facing regulators and mining companies for management and remediation of mining wastes. All mining waste units, including open pits, underground workings, tailings, waste rock and leached spent ore have the potential to generate acidic leachate based on the acid generation or neutralization potential of the material. This paper uses a case study of the Walker Mine in northern California to give an overview of the available control and mitigation methods. Wetland design is emphasized as a low-cost alternative treatment option for wastewater remediation. The Walker Mine is located on the eastern flank of the Sierra Nevada, 20 miles north of Portola in Plumas County, California. The Walker Mine was an active copper mine between 1915 and 1941. During active mining, tailings were discharged into an area 1 mile west of the site at the confluence of Dolly Creek and Grizzly Creek. In addition, there were two main sources of metal-rich, acid waters impacting Dolly Creek: discharge from the mine tunnel portal, and seepage and surface runoff from waters contacting mine waste downslope from the portal area. A mine portal seal was installed in 1987 which prevented the majority of mine water drainage from further contaminating the area. Minor drainage from the portal and seeps discharge into a holding pond which overflows into Dolly Creek when elevation exceeds 6,200 feet. A site characterization study was performed to evaluate the potential water quality threat to Dolly Creek from mine tunnel discharge and waste rock seeps. Based on the results of this study several remedial options were investigated, both on a design and cost basis, to determine which abatement alternatives could be realistically implemented. The remedial options considered include both in situ containment (landfill, waste pile) or removal (backfilling into underground workings and/or sinkholes) of solid wastes. Waste water remedial options include long-term, seasonal treatment of the portal mine water, or long-term, passive treatment of portal discharge and waste pile leachate.

Jan 1, 1993

By Carrie Smith

In a major milestone for geoscience, the U.S. Geological Survey (USGS) has unveiled the Cooperative National Geologic Map, the most detailed national-scale geologic map of the country to date. The project offers a fresh, layered look at the rocks and sediments that make up the United States. For geologists, engineers and mining professionals, it provides both a technical achievement and a practical tool that will help shape future exploration and landuse decisions across the country. The new map provides a regional view of geology both on and beneath the Earth’s surface. Using different colors to represent rock types and sediments, it allows users to toggle through multiple layers, revealing for the first time the surficial and quaternary deposits that lie above the bedrock. “This is the first national map to include multiple layers of mapped geology, the first built to be easily updated as new maps are published, and the first to be delivered in a user-friendly online interface,” said Joseph Colgan, a USGS research geologist who led the development team. The Cooperative National Geologic Map is a culmination of more than a century of collaborative mapping between the USGS and the nation’s state geological surveys. More than 100 existing maps produced by state geological surveys and the USGS over the past 40 to 50 years were combined and standardized to create the national data set. During its three-year creation, the USGS prepared digital data, built the system to bring the maps together, developed the web interface and underwent a review and approval process. Through this process, decades of fieldwork, analysis and digital cartography were brought together to provide both national and local expertise.

Nov 1, 2025

By Patricia O. Milley

Two years ago, AlliedSignal embarked on a journey to improve QUALITY. However, the focus of this endeavor was on the CUSTOMER and not the traditional product focus. It wasn't that a focus to improve product quality wasn't fruitful in the past. We've practiced it in the chemical industry for many years with significant results. But our industry today is in a survival mode and yesterday's way of doing business is simply not good enough. In the mining industry, we have to make lug strides in how we do business or face losing our customer base. As you are well aware, other parts of the world are importing our technology at a rapid rate. We must work smarter to stay ahead of our customers ever more demanding need for higher quality at lower prices. With this as a driver, throughout the Corporation we reviewed in depth how we support our customers to keep them competitive and sought to eliminate work which did not help them reach this goal. Our first year of emphasis was on tools: how to hold meetings, gather data, and how to make decisions. This sounds very basic, I know, but you can't begin to imagine how productive meetings can become when you start with an agenda and prework delivered days in advance, and agree at the start of the meeting what should get accomplished. In the second year, we applied these tools to our work processes. We mapped how we do our work, scrutinized each step for value to the customer, and then set to work on how we could do things better. The areas we concentrated on were customer linked commercialization of new products, manufacturing and materials management. Our discussion today will focus on the commercialization of new products.

Jan 1, 1994