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In late 1993, Inco Ltd. completed a $600-million environmental improvement project at its Sudbury, Ontario operations -the largest single environmental project ever undertaken by a Canadian corporation. Efficient new facilities and innovative technologies installed during the course of the project have also significantly improved Inco's productivity and competitiveness. In early May 1994, a panel of 18 Inco authors contributed to a Technical Forum, "Environmental Programs at Sudbury," presented at the 96th Annual General Meeting of the Canadian Institute of Mining, Metallurgy and Petroleum (CIM) in Toronto. Their papers have been published in CIM's Toronto `94 Proceedings Volume, pp. 62-77. The following report draws primarily on discussions of Inco's milling and smelting operations published in the Proceedings Volume. The Proceedings Volume also includes papers on the acid and oxygen plants and on engineering, construction and commissioning of the project. The 222-page Proceedings Volume is available from CIM, $C27 plus shipping. To order, contact: V. Ward, CIM, Xerox Tower, 1210-3400 de Maisonneuve Blvd W, Montreal, Quebec, Canada H3Z 3B8; phone 514-939-2710, fax 514-939-2714. Lane White, Publisher.

Jan 1, 1994

By Lawrence M. Lenahan

Cleveland's Southwest Interceptor Contracts No. 3 and No. 4 are continuations of Contract No. 1 addressed at the 1987 RETC with geology, equipment, and methods that differ greatly. The two contracts consist of 791 m (4.22 miles) of 3.5 m (11.5 ft) tunnel lined to 2.9 m (9.5 ft), nine access shafts, six drop shafts, and six collection structures. The excavation drive was completed by the use of a 1970 vintage Robbins TBM hybrid for this particular job through the use of both new and old technology. All other excavations were successfully accomplished through drill and blast method in tight residential areas. Concrete lining and connections were completed nine months after holing through.

Jan 1, 1989

By A. M. Esteves

This paper addresses the question ?What constitutes the right level of investment in community goodwill?? Mining companies are still grappling with this subject even though the business case for community investment has been accepted at a general level, as a strategy for competitive differentiation, risk mitigation and a desire to deliver - and to be seen to deliver - a ?net benefit? to affected communities. Gaining senior management commitment to long term social projects, by definition characterized by uncertainty and complexity, is made easier if projects are shown to benefit the site?s strategic goals. Case study research amongst mining companies, including interviews with social investment decision-makers, has assisted in developing a SI-DAT (Social Investment Decision Analysis Tool), a decision model for evaluating social projects in order to create value for both the company and community. Multi-criteria decision analysis techniques integrating business planning processes with social impact assessment have proved useful in assisting mining companies think beyond seeking access to required lands and peaceful relations, to how they can meet their business goals and contribute to regional development.

Jan 1, 2007

By Richard L. Wedertz

Although the physical appearance of excavating equipment doesn't seem to have radically changed over the past decade, important changes within the products and an innovative attitude on the part of the engineer in his design approach is becoming increasingly evident. The new philosophy is to go beyond simple refinements of existing designs that simply produce a machine which further reduces overall cost per ton or per cubic yard of material moved and to do it more efficiently than ever before. Standard ideas and preconceived notions have been discarded and have given way to providing a design and a machine that is best suited to get the job done. Understanding that the application will not always fit the machine, but, in most cases, the machine should fit or suit the application is a foremost consideration in the engineers' design criteria.

Jan 1, 1973

By H. Wesley Peirce

Although not generally recognized, Arizona has rock salt deposits unique in the United States. This uniqueness stems from a combination of two factors: (1) relatively youthful geologic age and (2) nonmarine origin. Although Arizona shares one deposit with Nevada (Figure 1, No. I) there are three others within the State (Nos. 2, 4, 5) that are believed to be both late Cenozoic in age (less than 15 million years) and nonmarine in origin. The only other recognized nonmarine salt deposits in the U.S. are much older, being in the early Cenozoic (Eocene) Green River Formation of Colorado and Wyoming. According to Johnson and Gonzales (1), the remaining rock salt deposits in the United States are marine and either Paleozoic or Mesozoic in age. Of the seven localities shown in Figure 1, six in the Basin and Range geologic province are believed to represent nomarine late Cenozoic phenomena and one (No. 7) in the Colorado Plateau geologic province is Paleozoic (Permian) in age and marine in origin. The following comments are intended to update the general geologic highlights of these deposits and to summarize the nature of their present utilization.

Jan 1, 1979

By Joseph B. Novak

In the last decade or so, the importance of effective preventive maintenance controls and practices has taken on a new and accelerated emphasis. Advances in technology and changes in equipment and product designs impose more precise and demanding standards of quality, productivity and customer service at a very rapid pace. Daily, it is becoming more apparent that in order to fulfill current requirements, existing manufacturing practices and associated control programs must also be upgraded and expanded. This is particularly true in the field of maintenance services. As production and quality standards become more demanding, effective equipment maintenance takes on more importance and becomes more difficult to sustain. In modern plants, the failure of a single equipment component can shutdown a complete production line causing interruptions to operating and shipping schedules that result in costly downtime, dissatisfied customers, and reduced profits. These costly experiences can be minimized with an effective maintenance program that provides maximum equipment reliability and minimum downtime and readily adapts to revision and change. A significant feature of an effective program is the provision of controls over activities generally identified as

Jan 1, 1971

By E. B. Kroeger

One of the problems encountered when constructing a roadway is the planned route often needs to cross soils that are soft and highly compressible. An approach to dealing with soft and compressible soils is to construct the fill from lightweight materials, thereby reducing the stresses on underlying soils. Most lightweight fills have approximately the same cost, so the most important consideration when choosing a lightweight fill is that the material properties of the lightweight fill match the conditions existing at the site. Expanded polystyrene (EPS) has been used as a lightweight fill material for more than 30 years. The EPS used for road fills is typically in the range of 0.5 to 2 lb/ft3, and has a compressive strength of in the range of 10 to 30 lb/in2. If a higher strength material is needed, then the material density is increased, which also adds to the cost of the material. Another type of lightweight fill material that is commonly being used is lightweight aggregate (LWA). LWA can be created by passing slate or shale through a rotary kiln or reheating coal fly ash with other materials to form pellets or aggregate. Several companies throughout the U.S market these materials under a variety of names. LWA can have a unit weight from 45-80 lb/ft3. For sites where trucking granular fill does not pose a problem, this material may be an alternative to EPS. One of the drawbacks to using LWA is the availability of the material. Only a few companies are manufacturing LWA, so it may not be available or may be cost prohibitive in certain areas of the country. Lightweight flyash blocks have been produced which may fill the gap in unit weight between the EPS and LWA. Blocks have been produced with a unit weight as low as 30 lb/ft3. They are relatively inexpensive, easy to handle, and have a moderate compressive strength. Although the unit weight is dramatically higher than EPS, the strength is also higher. If lateral stabilization of the fill is a problem, then geofabrics or grids can be incorporated into the design to add lateral strength.

Jan 1, 2003

By R. B. Massy-Greene

Project engineering and development is a process of optimisation of capital, operating and financial costs, and extraction rates in the light of current and forecast economic conditions for the sale of the product. The aim of the process is to maximize financial returns to the sponsors (project owners) within many often conflicting constraints. Thus, the sponsor's engineering and financial staff have a common goal, with performance measured in financial terms. Consequently, each group must be aware of, and responsive to, the constraints imposed upon the other. For financial staff, the increasing size and complexity, and escalating capital costs of new ventures have required them to seek finance in larger amounts, and by non-traditional methods. In addition, senior management are requiring indications of the availability of finance as a pre-requisite to a decision to commence project development activities.

Jan 1, 1982

By R. Jin

The hydrophobicity of six coals ranked from lignite to anthracite is studied through contact-angle measurements, bubble attachment-time measurements, FTIR spectroscopy, and Hallimond-tube flotation. The preliminary study shows that the hydrophobicity of coals can be told by the bubble attachment times of coals (a kinetic criterion) or by the contact angles (an - equilibrium criterion). A general agreement between flotation response of coals and measured bubble attachment times or contact angles is observed in the present study. However, the study also shows that the hydrophobicity of coals can be predicted by FTIR spectroscopy work with proper manipulation of the spectra. Both hydroxyl and carboxyl groups in the coals are proven by FTIR work to be responsible for the change of coal hydrophobicity. A new criterion for the hydrophilicity index of coals from FTIR spectra is introduced through the study.

Jan 1, 1987

By B. A. Barnum

The Chino mine is an open pit copper mine located in southwestern New Mexico, at an elevation of 1890 m (6200 feet) above sea level, approximately 117 km (70 miles) north of the Mexican border. It is owned by Chino Mines Co., a Phelps Dodge Corporation-Mitsubishi Minerals partnership, and is operated by Phelps Dodge Corporation. As part of an effort to maximize production and minimize costs, a computerized truck dispatching system was approved for purchase and installation at the Chino mine in March. 1984. Modular Mining Systems, Inc. was commissioned to install their system, trade named DISPATCH. The system installation was completed and operation began in July, 1985. Installation and operation of the system has presented some interesting challenges and problems, which have been overcome, resulting in increased productivity for the haulage truck and shovel fleets.

Jan 1, 1987

By Robert W. Gordon

The art of excavating tunnels with continuous, full-face boring machines began almost 90 years ago, in the early 1880's. At this time, Colonel Beaumont designed and manufactured a seven-foot diameter tunneler for boring under the English Channel, Despite the absence of modern materials and manufacturing techniques, Beaumont's tunneler, powered by compressed air piped in from the surface, was quite successful. During its short, but impressive existence, this machine set a record of advancing in chalk 50 feet per day for 53 days - which is impressive even by today's standards. Despite the apparent success of this early tunneler, almost 80 years passed before any further significant development was accomplished in this field. Demands from the construction and mining industry and society itself have motivated the development of the modern tunneling machine. Our rapidly growing civilization needs faster, less expensive and safer means of excavating tunnels. Space age technology and materials have played a major role in making hardrock tunneling machines possible.

Jan 1, 1970

By P. Soros

Rich iron ore deposits were discovered during the 1960's in the mountain range of Serra dos Carajas, State of Para, Brazil, near the headwaters of the Tocantins River some 400 miles southwest from the state capital of Belem. (See Fig. 1 and 2). The key to the successful exploitation of this deposit was the development of an efficient an economical transportation system. The rugged terrain, and the dense tropical vegetation of the Amazonian jungle and the irregular coastline with its high tidal range presented severe obstacles to the planning and building of such system. Starting in 1972 extensive surveys and studies were carried out by Soros Associates on behalf of CVRD to determine the optimum way of transporting the ore from the mine site to the markets, most of which are located overseas. Overland transportation to the coast, loading into seagoing vessels and the ocean voyage to the ports of destination was treated as an integrated system in these studies.

Jan 1, 1986

By Guocheng Pan

This paper presents-:a new multivariate mineral resource estimation model, referred to as the Related. Information (RI). Instead of relating a mineral resource descriptor directly to a set of geological variables, the RI model relates the mineral resource descriptor to a synthesized information measure RI, which is created from a set of geological variables. All of the variables are transformed into binary characteristics. This model comprises two stages of estimation: estimation of a synthesized information measure and estimation of mineral resources. The information carried by a variable is classified into three types: mineralized-barren information, mineral resource variation information, and variable-controlling information. The synthesized information measure is defined as the product of the three types of information and the responses of binary geologic characteristics. The RI model is demonstrated on the pegmatitic Nb+Ta deposits in China.

Jan 1, 1992

By Alejandro Prieto

Traditionally, Mexico has been a mining country. This industry has played a very important role in our country's development, creating jobs, integrating geographical regions - generally very remote from urban communities - and, an essential factor in our present day economy, generating an influx of foreign currency. The Fluorspar mining industry's development started in the 1920?s, but it was not until World War II that its exploitation became consistent and started growing. During the last few years, Mexico has become the world's leading producer, with an annual output of more than one million tons, which directly generates over 3,000 jobs. The actual proven reserves can guarantee fifty years of production at this same annual rate, and it is due to this fact that the producers have not increased their reserves. However, there is concrete information of the existence of several deposits, extending from the northern border to the gulf of Mexico, forming the "Fluorspar Belt? in Mexico.

Jan 1, 1986

By Alfredo Menendez, Alberto Sarmentero

A B S T R A C T The Los Pijiguaos bauxite is one of the largest accumulations of trihydrate alumina ore recently discovered; it is a plateau type, with no overburden, relatively soft tertiary quartz-bearing bauxite developed on a pre-Cambrian Rapakivi Granite batholith. The deposits are found in the northwestern rim of the Guiana Shield, State of Bolivar, Venezuela, and were discovered in 1976 after a grass-roots exploration campaign. Target areas were mainly selected on the basis of geological and geo¬morpholigcal criteria, guided by correlation with known deposits elsewhere in the Guiana Shield. The vertical. lateritic profile consists of an upper concretionary zone, followed by a mottled zone, a palid zone and finally the weathered rock merging into fresh granite. The upper concretionary zone displays a cellular, pisolitic or spongy texture and contains the following minerals: gibbsite (60-90%),quartz (5-10%), hematite (5-10%), goethite (under 5%), boehmite (traces), kaolinite (traces). The gibbsite content decreases sharply downward from the lower limit of the concretionary zone and the kaolinite and quartz content increases in the underlying mottled zone. The mottled and palid zones display a pseudo rapakivi texture and quartz, kaolinite and mica are the. essential minerals.

Jan 1, 1984

By Terry S. Maley

With some exceptions, minerals may be acquired on the unappropriated public lands by one of three methods: (1) mining claim location under the General Mining Law of 1872; (2) mineral lease under the Mineral Leasing Act of 1920; and (3) sale contract under the Mineral Materials Act of 1947. Leasable minerals such as oil, gas, coal and phosphate are specifically designated as leasable in the Mineral Leasing Act so the method of acquisition is clear. As a general rule, metallic minerals are acquired by mining claim location. However the nonmetallic minerals, most of which are industrial minerals or gemstones, present a more difficult problem. These minerals are acquired either by mining claim or a sale contract depending on their chemical composition, physical properties and the use to which they are put. The Act of July 23, 1955 (30 U.S.C. 61 1) provided that uncommon varieties of sand, stone, gravel, pumice, pumicite or cinders are locatable; whereas, common varieties of such minerals may only be acquired by a contract of sale. The widespread location of mining claims to appropriate such deposits has caused many land management problems. Federal court and Interior decisions offer the most useful guidelines in determining the most appropriate method of acquisition.

Jan 1, 1991

By Randall E. Brown

Irrigation simulates a climate change so that crops can be grown that otherwise would not thrive. The abundant sunshine and warm weather of many arid regions induces a rate of growth in excess of that in cooler, moister regions. Hence, the arid part of eastern Washington, traversed by the Columbia River, is admirably suited to irrigation. The Pasco Basin lies in south-central Washington at the south end of the Columbia Basin Irrigation Project of the U.S. Bureau of Reclamation. The Basin, because it lies in the rain shadow of the Cascade Mountains, receives only 6 to 10 inches of precipitation a year with somewhat greater amounts, commonly as snow, on the higher hills. Recent extremes included 3 inches of precipitation from August 1967 to August 1968, and 12 inches in the succeeding "12 months. Most of the precipitation falls during winter. If it were to fall in summer or were evenly distributed throughout the year, evaporation rates probably would produce a true desert.

Jan 1, 1971

By Andrzej Wala, Henry P. Cole, Perry David Passaro

Cognitive representations and misconceptions of flow through circuits is an area which has received little attention from science educators, cognitive psychologists, or accident investigators. Misconceptions are also called Aristotelian thinking. They involve a person using primitive unscientific ways of reasoning to make decisions about events (Piaget, 1929; Nussbaum & Novick, 1982; McCloskey, 1983). The use of such primitive concepts leads to errors in reasoning about scientific and technical problems. The existence of misconceptions is well documented among children, adolescents, and adults involved in learning science concepts (Piaget, 1929; Cole & Raven, 1969; Clement, 1982; Mistrell, 1982; McDermott, 1984; Richardson, 1987). Concepts of flow through circuits are important because miners' conceptual errors about these aspects may be, in part, responsible for two fatal mine disasters. On at least two separate occasions, methane gas explosions occurred in underground mines when separate ventilation systems were connected (Elam, Fuller, Carter, Cavanaugh, Fesak & Painter, 1983; Fesak & Cavanaugh, 1984). A review of these disasters indicates that conceptual errors made by miners may have resulted in the accidents (Cole, Wala, Haley, & Vaught, 1987). In this study, co-author Andrzej Wala, stated that his research had "identified conceptual errors that may have caused the miners in these disasters to make fatal mistakes" (Cole et al. 1987), p. 167. Further exploration of these conceptual errors by Wala has led to the hypothesis that misconceptions of basic aspects of flow distribution changes in mine ventilation circuits, are at least, in part, responsible for some mine disasters caused by errors in ventilation systems (Wala & Cole, 1987). Why should these conceptual errors occur? Ausubel (1963) suggested that students come to a new area of study with their own conceptions or preconceptions about how a process operates. Furthermore, these preconceptions may be in conflict with the empirical data from the discipline. In such cases, learning becomes a process in which new concepts must displace or be re-molded from stable concepts that the student has constructed over many years (Clement, 1982). Given the existing research with misconceptions and the work of Wala and Cole (1987), it was hypothesized that experienced miners; either working miners, students of mining engineering, or professional mining engineers, harbored misconceptions about the formal or conceptual aspects of mine ventilation circuits. The misconceptions hypothesized to exist involved flow distribution changes in complex mine ventilation circuits; specifically, how does flow distribution change when a ventilation circuit pathway is altered? Given this information, the following research questions were proposed. Research Questions 1. Do experienced miners and mining engineers harbor misconceptions about mine ventilation systems? This question was addressed by: A. The administration of the Cutthrough Ventilation Arrangements (CVA) exercise that measures subjects' performance level when making decisions about major ventilation changes when connecting two mine sections;

Jan 1, 1989

By M. García-Vásquez

In Peru, the third destination in worldwide exploration based on expenditure, mining conflicts have spread dramatically over the last decade. Mining companies need to create new initiatives to avoid social conflicts and strengthen the social capital needed to keep mining in a country with proven mineralogical riches. This document provides information about a research project that explored the opinions and experiences of a resource many times overlooked by companies: the human resource. Over 30 surveys were conducted among professionals working at mines in the Peruvian mining industry, in different departments and from different organizational levels. Mining employees acknowledged that they play an important role in the development of company-community relationships and gave their impressions about initiatives implemented by international mining companies in Peru. Mining employees also provided their recommendations to succeed in a location where cultural differences have not been properly considered.

Jan 1, 2011

By N. S. Tanious

Three water-spray ventilation systems were tested to determine their effectiveness in diluting methane at a room and pillar coal mine face. These systems were: the shrouded nozzle, the spray fan, and the conventional nozzle system that is normally supplied with continuous miners. The testing was carried out in two stages. The air-moving capacities of the nozzles were first evaluated in a duct. The duct tests showed that: (1) the volume of air moved by the nozzle is controlled by the type of nozzle, the space around it, and its location relative to the duct wall; (2) the spray fan nozzles or the shrouded nozzles are both capable of moving air quantities up to 6400 cfm (3.02 m3/s); and (3) when the shroud was removed from around the shrouded nozzle, its bare nozzle moved between 9 and 65 percent more air. In the second stage of testing, a full-scale evaluation of the three systems was conducted. The three spray systems were mounted on a continuous miner which was positioned in an aboveground simulated mine entry. The simulated face tests gave the following results: (1) the standard nozzle system, which is mounted on the front end of the miner, is inadequate for diluting methane; (2) under the best testing conditions (lowest methane emission rate, highest primary ventilation airflow, and closest brattice set back), the slight improvement given by either the shrouded system or the spray fan is the same; and (3) under the worst testing conditions (highest methane emission rate, least primary ventilation airflow, and farthest brattice set back), the spray fan gave superior performance.

Jan 1, 1987