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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 J. J. Scott, G. H. Bennett

INTRODUCTION Friction Rock Stabilizers, commonly called Split Sets,tm* have been under development since early 1973. Five years of intensive laboratory and field testing led to their introduction to the metal mines in the United States in the fall of 1976. Actual sales started in February of 1977 and, to date, over five million units have been marketed to metal mines. The present rate of useage is near 3 1/2 million units per year which is approximately 50 per cent of all roof fixtures used in the United States metal mining industry. Mr. Richard Hoppe, Senior Editor of Engineering & Mining Journal, in an article of the February, 1979, issue, entitled "Winning the Battle Against Bad Ground", said, "In hardrock mining operations in the western U.S., particularly underground uranium mines where exceedingly difficult ground is common, no roof support system has been accepted more quickly than the Split Set friction bolt invented by Dr. James J. Scott and developed by Ingersoll-Rand Co." This paper describes how Friction Rock Stabilizers function and presents technical data to show the uniqueness of the Friction Stabilizer system. SPLIT SET STABILIZERS The Split Set System is a revolutionary development in the field of ground control. The system produces an interior reinforcement to a rock mass which: *Trade Mark of Ingersoll-Rand Co.

Jan 1, 1979

By Peter Erlynne

Rising costs have affected the cost of operating and install­ing crushing circuits, just as they have affected every other area and there is little possibility that the cost cycle is about to be reversed - power costs, wear materials costs and labour costs continue to increase but a basically stable gold price makes little allowance for these cost increases. Additionally, lower grades of ores being worked, and harder feed materials have a significant effect on the potential for higher processing costs. There are, of course, options for size reduction - some of them newer than others - some are suitable for certain types of ores and less suitable for others and it can sometimes be difficult to ascertain the accuracy of anticipated results before plant design and con­struction are completed - by which time the capital outlayed will preclude a change to another method ofreduction. Nordberg's patented WaterFlush Technology has the potential to change the way that Ball Mill Feed production is viewed: Some of the elements that must be considered are: • Capital Cost • Operating Cost • Efficiency • Flexibility • Availability • Control • Support Efficiency • Expertise • Spares availability • Environmental considerations

Jan 1, 1995

By Robert L. Sandefur

Geostatistics of coal thickness and quality parameters for various coal seams in the San Juan Basin of New Mexico are reviewed. Interpretation of the histograms, variograms, and drifts of the data in the context of depositional environment and post-depositional geological history is discussed. A multivariate geostatistical technique for checking the accuracy of seam correlations is demonstrated.

Jan 1, 1982

By Lynn B. Hales, Randy A. Ynchausti

Introduction There continues to be a large economic opportunity associated with improving process performance through advanced process control systems within the minerals industry. The basis for this opportunity lies in the inherently low efficiencies of many of the unit operations found in mineral processing plants as well as the continual variation that is present in the ores being processed. The ageless target of such control systems is improved recoveries and concentrate grades, higher processing rates and lower unit costs. Many plants are enjoying the benefits of modem, well functioning process control systems but few if any have achieved plant-wide optimization in an economical sense. As new process modeling and control technologies, such as neural networks, continue to evolve and develop, the potential for plant- wide optimization is becoming a closer reality. Neural network technology appears to have a significant potential in the general field of process control and control of mineral processing operations. Neural networks are an emerging technology that have been evolving out of the study of biological systems since the early 1940's. The first software simulation of neural computing networks was reported in 1956 by Nathanial Rochester of IBM Research during the first conference on artificial intelligence which was sponsored by the Rockefeller Foundation. Neural Networks Neural networks can be considered to be a class of computer program that perform their problem solving functions based on a rudimentary model of the human brain and how it solves problems. Traditional computer programs and even computers themselves solve problems or process data sequentially and in a deterministic manner. The human brain, on the other hand, processes data and solves problems in a massively parallel fashion. We think of computers normally in terms of having a single processing unit, sometimes a co-processor to assist in certain activities such as mathematical functions or communications, bytes of memory, processing speed and program/data storage size.

Jan 1, 1992

By T. Simpson

European industrial policy seeks to provide the right framework conditions to allow companies to develop and innovate and to make the EU an attractive place for job creation. This includes providing the basis for a competitive manufacturing industry which provides around 20% of EU economic output and employment for about 34 million people. The EU non-energy extractive industry with an annual turnover of around ?40 billion and a direct workforce of about 270,000 people is considerably smaller, but it plays a vital role in providing much of the manufacturing sector with raw materials. It also supplies very large quantities of minerals such as aggregates and natural stone to the construction industry, facilitating the development of modern infrastructure such as roads, railways, houses, schools and hospitals. However, despite an active extractive industry, Europe is increasingly dependent on imports of raw materials and particularly metallic ores and concentrates. In 2005, the trade deficit for minerals was in excess of ?11 billion, of which ?10 billion related to metallic minerals. Such import dependency is not a new phenomenon, but the rapid industrialisation of developing countries such as China and India has significantly increased global demand, resulting in large price increases for downstream industries and at times, bottlenecks in supply. The impact of this and other competitive pressures on some sectors of the European manufacturing industry, including the possibility of them being lost to lower cost countries outside Europe, has moved the issue of industrial policy and access to raw materials up the political agenda. A number of measures have already been announced by the European Commission to address these issues including: - The analysis of the competitiveness of individual industrial sectors, in order to understand their specific needs and take account of the particular opportunities and challenges they face.

Jan 1, 2006

Due to the relatively remote location of the St. Anthony Mine, the high cost of transportation and milling, plus the low grade nature of the deposit, the United Nuclear Corporation began investigating methods of mechanical upgrading approximately eighteen moths ago. This investigation culminated in the installation of Model 17 and Model 18 ore sorting machines. The machines are marketed in the United States and Canada by Ore Sorters of Canada (Ltd.). The installation of this advanced technology will enable United Nuclear Corporation to fully realize the residual potential of St. Anthony.

Jan 1, 1979

By Ruston A. Ford

This paper reviews the development of the David Bell Mine, from early exploration, through discovery, construction, start-up, underground development, and production. Details are provided regarding the mine development, the mechanized cut and fill stope production, the proposed long-hole stoping with delayed backfilling mining method for the lower levels and the cyanide leach carbon-in- pulp concentrating process. The mine development remains on schedule and under budget with results very much as predicted in the feasibility study.

Jan 1, 1987

By J. Stachurski, N. A. Abdel-Khalek

Laboratory Potation tests were carried out on six Polish coal samples of different rank. Each coal sample was screened into seven size fractions. The floatability of size- by-size for various size ranges for different samples was investigated as well as for the original samples. The results showed that in flotation of size-by-size, the intermediate sizes varied with the rank of the coal. Entrainment was shown to be an important mechanism in the recovery of fine particles in flotation of the original samples.

Jan 1, 1991

By Hilal Soydan, H. Sebnem Düzgün, Jurgen Brune

In this study, with the primary goal of capturing ongoing digital transformation and automation impacts on the mining industry and its workforce, we conduct several interviews with mining industry experts in the United States and analyze our survey reports qualitatively and quantitatively through exploratory analysis. After the interpretation of the insights of industry experts, we proceed to generate a personalized and customized data analysis through a novel metric based on skills, knowledge, competencies and occupational requirements, which quantifies the job similarities for occupations in the mining industry based on the publicly available database of the U.S. Department of Labor. We use text analytics to tokenize and classify the interviews to capture a better understanding of major response categories. The temporal analysis shows that the critical competency needs in the data science and autonomy category increases from 28 percent in current demands to 43 percent. In defining our metric, we also calculate Kullback–Leibler (KL) divergence for each job profile that enables determining whether and to what extent that job is transitionary in our test set based on the mean, standard deviation and kurtosis of each job of interest. Our analysis reveals that the in-group job transitions are significantly easier than the between-group transitions, proving our initial assumptions and common sense. The generated heat maps provide the opportunity to present the gap between the current job and desired job profiles that provide feasible career change options, among others, offering individualized career paths for job seekers and promoting potential job transitions. Through the collection of industry-specific individual employee data, the AI system is envisaged to continue to learn as end users engage with the system, thus creating a central data hub specifically for the future workforce in the mining industry. Although the study has limitations on generalizability for qualitative assessments, it presents itself as a valuable application of how qualitative and quantitative approaches could be of value for future worker training in the mining sector.

Feb 1, 2025

By D. B. Ogbenlowo

A major problem facing the Nigerian Mineral Industry today is flooding in its underground mines. Flooding has reduced productivity to a very low level which results in huge economic losses. Consequently, this paper presents a computer based model that pre¬dicts the quantity of water accumulating from diverse sources in an underground coal mine with a view to suggesting a permanent solution to the problem. Specifically, the paper describes the model building technique and the output achieved from its application to a real mine case study.

Jan 1, 1988

By Dennis P. Bryan

Natural lightweight aggregate may be defined as inherently low density natural mineral materials. In most all instances they are relatively young volcanic rocks which, because of their geologic environment, are limited to the Western U.S. These Tertiary and Quaternary volcanics are low-density glass and vesicular material including, but not limited to, pumice and volcanic cinder. The distribution is widespread throughout the West with the principal producers being New Mexico, California, Oregon, Idaho and Arizona. The primary user is the construction industry where weight reduction equates to cost savings. Principal products in which natural lightweight aggregate is utilized because of its lower density include lightweight portland cement concrete and lightweight concrete masonry units. In addition, due to location, some natural lightweights compete with normal weight constructions aggregates for uses such as road base and common backfill material.

Jan 1, 1989

By R. L. Pozzo, I. Iwasaki

A previous investigation showed that corrosion currents estimated from polarization curves for the pyrrhotite-grinding media system under abrasion correlated well with corrosion currents estimated from marked ball wear test data by applying Faraday's law. Freshly abraded metal debris were magnetically attracted to pyrrhotite and lowered the rest potentials of the mineral particles, thereby affecting the corrosive wear. The investigation was extended to explore the interactions between a non- magnetic sulfide mineral, pyrite, and abraded metal debris and their effects on the corrosive wear mechanism. The electrochemical behavior of a three-

Jan 1, 1988

By P. C. Cochrane, I. S. Clelland, S. H. E. Phillips

Geological and hydrological conditions in the strata overlying the Salado Formation vary considerably in the Carlsbad, NM, area. The first four shafts sunk at International Minerals and Chemical Corp. (IMC) property have been located in competent and essentially dry conditions, while other shafts on adjacent properties have had such adverse conditions that ground freezing has been chosen as the water and ground control technique for shaft sinking. At the location of the IMC No. 5 shaft there has been extensive erosion and salt dissolution in the Rustler Formation, leading to collapse of some zones of the strata. Both ground freezing and pregrouting were considered as alternative methods of stabilizing the extremely poor ground conditions and controlling the potentially very heavy water inflows. It was decided that pregrouting the shaft was feasible and would offer substantial cost and time saving over a ground freezing technique. This paper describes the pregrouting techniques used and illustrates the requirement for flexibility in a grouting program so that it can be modified to reflect any new or additional information obtained during the progress of the grouting.

Jan 1, 1987

By M. Kyzeridi

The paper presents a study on the reclamation of two mined-out bauxite open pits in the area of Kefali, Itea, Greece. The mining area has been reclaimed partially in the past, but its proximity to the town of Itea and a national road with tourist traffic, rose the interest to examine various scenarios for improving the landscape and the aesthetics of the site and introducing alternative land-use for recreational activities. Geospatial data were modelled using a Geographical Information System (GIS) that made it possible to study alternative proposals in terms of final landscape profiles, volumes required to be moved and the associated costs.

Jan 1, 2002

By R. M. Ocampo-Franco

The line seven, as part of the development of the Subway Master Plan in Mexico City, will tunnel under different subsoil conditions of clay with high water content and low shear resistance located between 8 and 12m beneath the surface. Boulders in silty sand and gravel to a 40m depth underlay this stratum. Economics, scheduled time of construction, and the obligated interconnection with existing lines one and two determined the construction of the tunnels to have an overburden of 1.0 to 2.2 times the diameter. In the north part of line seven there is a track of 251m length that was decided to attack with an open shield of 9.14m of diameter due to the characteristics of the sub-soil, minimum section needed as well as a minimal overburden, of 10.41m. The paper explains the construction procedure from the excavation stage to the reinforcement of the final lining obligated for the ground subsidence as a result of volumetric changes of a stratum of 4m thick of clay overlying the crown of the shield. Manuscript not received in time for publication.

Jan 1, 1983

By A. N. Islam, C. Simons, M. N. Hughes, J. Barrett

The effluent from the bio-oxidation of arsenopyrite contains high concentrations of iron(III) and arsenic(V), the pH being in the range 1.0-1.3. The use of lime to increase the pH causes the precipitation of calcium sulfate, calcium arsenate and a mixture of solids containing calcium, iron and arsenic. The presence of calcium is due to slaked lime encapsulated by the iron arsenate precipitates. These iron arsenate solids are related to known minerals. The use of sodium hydroxide to effect the precipitation of iron and arsenic produces solids which are more stable than those produce by using slaked lime. The use of limewater produces an initial precipitate of calcium arsenate.

Jan 1, 1991

By B. van der Moolen, P. J. M. Groot

The introduction of liberalisation in Dutch mineral provision has created a lot of uncertainty on how and where to supply for the need of construction raw materials. Some possible effects of this policy shift are: 1. the extraction of materials from small pits with truck transport, 2. an increasing dependence on foreign suppliers, 3. the usage of marine dredged materials, 4. more input of secondary substitutes. The outcome of this policy and the resulting marketbehaviour have consequences for transport and infrastructure and hence for sustainability issues. Mineral provision, on the other hand, is also influenced by the availability of infrastructure. Insufficient transport capacity could hamper the development of mineral projects that render benefits to society. (Even) in a liberalising market for mineral provision, the central and local governments have an important role to play with regard to infrastructure and the effects of transport. Various trends point towards an increasing internationalisation in mineral provision. What will increasing trade and increasing influence of the market mean for transport infrastructure? How should increasing transport be judged with respect to sustainability? In the sustainability discussion these questions will have to be answered on a national as well as on a European scale.

Jan 1, 2005

By James M. Prudden, E. P. Jucevic

The Divide mining district occupies the center of a Tertiary caldera hosting the famous Divide silver lode and the crosscutting Gold Mountain mines. The northwest-southeast trending silver lode hosted ore with typically a 100:1 silver:gold ratio, high molybdenum content and argillic alteration dated at 16.5 m.y. within the Fraction Tuff. The east-west trending Oddie Rhyolite flow dome at Gold Mountain experienced possibly several periods of resurgence with repetitive silicification, brecciation and attendant precious metal deposition forming stockwork type mineralization. Silver-gold ratios average 10:1 for the mineralization phase of this 16.4 m.y. intrusive event. Similar chalcedonic mineralization registering a 3:1 silver:gold ratio cements conformable breccias within the Oddie Rhyolite basal flows unconformably overlying the Siebert Tuff on the northern flanks of Gold Mountain. Gray and red chalcedonic breccia matrix in the King Tonopah member of the Fraction Tuff contains a 50:1 silver :gold ratio.

Jan 1, 1990

By A. M. Stone

Following the conceptual idea of a Continuous Elution Process early in 1982, the system was successfully pilot plant tested at Western Mining's Kambalda gold plant in December 1982. As a consequence of these tests the Ok Tedi elution ciruit design was changed from batch operation to continuous operation resulting in a reduction in the number of similarly sized elution columns from five operating with one standby to one operating with one standby and halving the process steam requirements. In addition to providing significant capital and operating cost savings the continuous process was simpler to operate than the batch process.

Jan 1, 1989