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By James D. Bennett, David L. Passmore

The Coal Mining Section of the National Safety Council has selected hand and finger injuries of coal miners as a major topic for safety policy analysis [Tinney, 19851. So that facts about hand and finger injuries can be used to guide the Committee's work and the work of policy-makers, we present in this paper detailed analyses of the following factors related to hand and finger injuries received by coal miners between 1975 and 1983: occupations of the injured miners; activities of the miners when injured; machines involved; objects, substances, exposures, or bodily motions that produced or inflicted the injuries; principal physical characteristics of injuries; and events directly resulting in the injuries. We analyze hand injuries for underground and surface mines separately because of the remarkably different production methods and hazards evident in these two operating environments. We do not, however, provide information about hand and finger injuries that occurred in surface operations at underground sites (such as yards, shops, or tipples), auger mining operations, culm banks, dredging operations, mill or preparation plants, offices, or laboratories. The most comprehensive information about the safety of coal mining in the United States is assembled by the Health and Safety Analysis Center (HSAC) of the Mine Safety and Health Administration of the United States Department of Labor. Mine operators in the United States report to HSAC all injuries as required under Part 50, Title 30, of the Code of Federal Regulations (mandated by Section 103 the Federal Mine Safety and Health Amendments Act of 1977, Public Law 95-164). These regulations stipulate that injuries must be reported within ten days of their occurrence on a United States government data collection form, Mine Accident, Illness and Injury Report (MSHA Form 7000-1). HSAC maintains these data primarily to produce federally-mandated reports. HSAC resolves injury reports that are incomplete, checks for errors in data coding and handling, and corrects inconsistencies in data submitted by

Jan 1, 1986

By Francis R. McAllister

SYSTEM ENGINEERING Years ago, while attending Harvard's Advanced Management Program, Professor Robert Hayes introduced our class to the, then not-so-familiar, concept of systems engineering. First assignment-dinner at The Benihana of Tokyo Restaurant! Delighted, but a bit mystified with the assignment; we had dinner at Benihana. Back in class, Professor Hayes inquired about the assignment and persuaded us; that Rocky Aoki's business formula for Benihana was not necessarily Japanese cuisine, but rather the systematic way in which he moves more people-if you will, processes more people through his restaurants than his competition, by systematically linking all restaurant functions. For instance, the bar is a holding area in which patrons ideally wait no more, or no less, than 20 minutes. When seated, your table, which accommodates eight, is filled with eight even if you are a party of two. The Japanese chef is also the entertainment, and when, at the end, he cleans the grill, you are being subtly prompted that dinner is over. The bill accompanies ice cream, systematically delivered shortly thereafter. You are expected to pay promptly and depart, as there are eight more, mostly unacquainted, people who have waited 20 minutes in the bar, and who are assembled ready to be seated at your table. For me-this was electrifying. I understood the concept, concluded it was very powerful and felt prepared to conquer whatever, by means of its application. That was years ago and I can safely say I have yet to fully realize on the euphoria of that moment. Why? Well, I simply conclude: • The concept of systems engineering is simple and not revolutionary, but The application of systems engineering is far from simple and is revolutionary.

Jan 1, 2004

By Bhaskar B. Thapa, Michael T. McRae, Michael J. Teske, Richard M. Nolting

Packer test data and tunnel in?ow observations are used to show that the distribution of equivalent hydraulic conductivity obtained for a rock mass from borehole packer testing will be biased if the orientations of the planned tunnel and testing borehole differ. Furthermore, test results show that the distribution of equivalent hydraulic conductivity is different in various geologic sub-units at the same site. The impact on in?ow of the major uncertainties, including conductivity, head and specific yield, is illustrated to be amenable to a combined analysis using Monte Carlo simulation.

Jan 1, 2003

By Xinming Lu

In this paper, we use a new kind of fan charateristic curve instead of the common quadratic function, and give the existence and the uniqueness of the solutions to the ventilation network controlling equations, so that the existence and the uniqueness of the solutions for the natural air distributting problem can be conveniently given. We also give a conjugate gradient method with the global convergence to solve the equations having the unique solution. Because we adopt a very efficient technique of one dimensional search (or linear search) in this method, the method can quickly solve a lot of problems, especially in large scale problems. The second part of this paper is the establishment of the model of the constrained quadratic programming for the measurement adjustment of mine ventilation network. We give the algorithm to solve this model as well. The two algorithms given above have been realized in the mic-computer MC-68000 with Fortran codes, and the numerical results are satisfactory.

Jan 1, 1991

By A. M. Johnson, D. H. Carlson, D. L. Johnson, S. T. Bagley

A biologically assisted ferric iron leaching system was evaluated for in situ recovery of three copper sulfide oresfrorm northern Michigan. Laboratory scale bacterially assisted ferric sulfate leaching tests were run on the three ores. A T. ferrooxidans strain was found that could be adapted to copper in solutions at concentrations as high as 20 g/L. Column leaching of 4.5 to 2 mm (-4 +I0 mesh) material yielded extractions of 80-90% copper from one ore and 70 and 60% from the other ores. The highest copper extractions were from the Mount Bohemia ore deposits located in the Keweenaw Peninsula, which have fracture controlled chalcocite mineralization. The Bohemia ores are apparently well-suited for in situ solution mining.

Jan 1, 1987

By W. R. Dearman, N. Turk

The theoretical relations between the strain and stress Mohr circles make it possible to establish a relation between the internal friction angle [ ] and the Poisson's ratio (v) of rocks. The internal friction angle is related to the Poisson's ratio as Sin [-] = (1 - v)/(l + v). This relation gives lower friction angle values than the triaxial Mohr envelopes and higher values than those given by surface sliding friction tests.

Jan 1, 1986

By John D. Abbatt, H. B. Newcombe

The Eldorado Epidemiology Project formally began in late 1978. It consists of a retrospective cohort study, to be followed by and to leave in place the mechanism for a prospective cohort monitoring program. These present and future activities are intended to merge into one another. The current study includes all Eldorado employees past and present for whom records are available. The objectives of the undertaking are - 1) to obtain cause-and-effect, dose-response data with which to evaluate the risks to workers in radon and radon daughter containing atmospheres, and to provide additional quantitative information on which to base possible improvements in working conditions; 2) to identify any dead employees of E.N.L. whose cause of death suggests that a potential compensation claim right exists for their survivors, and to similarly identify living ex-employees of E.N.L. whose work histories and states of health suggest potential compensation claim rights. The nature of the study has been determined by the history of Eldorado, which will be described briefly. Eldorado began (as Eldorado Gold Mines) in the late 1920's, operating relatively unsuccessfully in Manitoba. In 1930-31 the emphasis shifted from gold to uranium, and what became the Port Radium mine was first staked. From the very early 1930's until 1942 the company's purpose was almost entirely devoted to the mining of pitchblende - uranium ore - from the Port Radium site, and the extraction of radium from this ore at the Port Hope refinery in Ontario, a process from which the uranium was a largely stockpiled byproduct. In 1942 the company was requested by the Canadian government to accelerate the production of ore, and of uranium. At the same time, all its stockpile of uranium (then being stored in silos as a "waste" product which might later "come in") was acquired for the Manhattan Project. In 1944 the company shares were bought by the Canadian government and the company itself became Eldorado Mining and Refining (1944) Limited; it has operated as a Crown corporation ever since. The name was changed to Eldorado Nuclear Limited in 1968. The Port Radium mine was closed in 1960, and since 1953 the Beaverlodge uranium mine complex has operated on the northern shores of Lake Athabasca. Radium production was discontinued in 1954 when the radium circuit was taken out of the refinery, and since that time the refinery's products have been various types of refined uranium (uranium dioxide, uranium trioxide and uranium hexafluoride) plus metallic uranium. The refinery, of course, processes the company's own yellowcake but as it is one of only five refineries in the western world, most of its work consists of custom refining for a large variety of customers. In addition to the mining and the refining operations, there have been three other divisions involved, and these are, respectively, Aviation, R. & D., and Exploration, in addition to the financial, corporate, administrative and support activities. MATERIAL AND METHODS The human study population (Abbatt, J.D. et al., 1980) consists of all Eldorado employees who have ever worked for E.N.L. and for whom records are available. The total nominal roll to December 31, 1980 is approximately 21,000 and consists of employees of the Mining, Refining, R. & D., Aviation and Exploration Divisions, as well as a relatively small number of other employees (Head Office, etc.). The basic epidemiologic design, as has been mentioned, is for a retrospective cohort study merging into a prospective cohort study, and depending very heavily upon automated record linkage and file matching. The original design called for an initial assembly of the bulk of the nominal roll, prior to the first of two matches with the National Mortality File. The first of these two matches is now complete and the second is to be separated from it in time by 18 months to two years. The second match will be the definitive match prior to the analysis, the interpretation of the data, and the publication of the results. The period between the two matches was designed to permit completion of the nominal roll, including: - addition of previously missing individuals and groups, elimination of duplicates, and amplification of identifying information, - assembly of work histories and exposure information for each individual, - digestion and application of lessons and modifications resulting from the first match with the National Mortality File at Statistics Canada, - preparation of files for the definitive second match. The analysis of data will be carried out by the National Cancer Institute of Canada Epidemiology Unit based at the University of Toronto. This group, with whom Eldorado Nuclear has a memorandum of understanding, have for a variety of reasons, including their familiarity with record linkage and their expertise, been members of the Project Team since

Jan 1, 1981

By P. J. Suardini, S. K. Kawatra

A number of on-stream coal slurry analyzers are presently being developed and commercialized for measuring ash and solids in coal process streams, particularly around flotation circuits. The eventual goal of these efforts is to develop on-line quality control systems for flotation circuits and other fine-coal cleaning operations. As part of this on-line monitoring and control effort, it is important to gain a better understanding of the response of industrial flotation circuits to changing operating conditions. This paper summarizes the results from a detailed sampling program performed at an industrial coal flotation circuit in western Pennsylvania. The testing focused on evaluating the response of the circuit to changes in reagent dosages, operating conditions and feed compositions. The testing indicated that it is desirable to maintain high collector-to-frother ratios to enhance coarse particle flotation. The recovery of fine impurity particles was also proportional to water recovery, due to hydraulic entrainment. Key words: Industrial, Coal, Flotation, Circuit, Reagent, Response.

Jan 1, 1995

By R. Todd Swinderman

Impact cradles are installed below the belt in conveyor loading zones to cushion the forces from material loading. In this paper, the author will discuss the need for and then explain the new CEMA standard for engineering of impact cradles. He will review the engineering theory and work through an example to demonstrate the assumptions used in the standard do not inappropriately affect the CEMA rating system.

Jan 1, 2002

By John P. Albers

During the 1950's and 1960's a program of geologic mapping of counties has been underway in Nevada by geologists of the U. S. Geological Survey and the Nevada Bureau of Mines. The aping has been done principally at reconnaissance scales, with more detailed work in local areas. Geologic maps are either published or open-filed for about a dozen counties at scales of 1:200,000 or 1:250,000. One by-product of the geologic mapping has been the recognition of about 80 Tertiary volcanic centers from which large or very large volumes of volcanic material ranging from rhyolitic to andesitic in composition have been erupted. For purposes of this discussion these are regarded as the major centers; the tally does not include hundreds and perhaps thousands of small rhyolitic domes and plugs and basaltic vents. About 15 to 20 of the 80 major centers are believed to be calderas ranging in diameter from 3 to 25 miles. Some have been described in the literature by geologists of the Nevada Test Site and others. However, the vast majority of the 80 centers have not been described in print, and we are indebted to our colleagues for locating them for us in many of the counties. Briefly, we would like to express our appreciation to the following people all members of the USGS unless identified otherwise: Robert Coast, who has identified the centers in Elko County; Ron Willden, Robert Yates, and

Jan 1, 1968

By John Marsden

JIM ARNOLD: Our next speaker is John Marsden. John runs the concentrator complex at La Candelaria Project in Chile. John's a Royal School of Mines graduate and he wrote the book on gold metallurgy, The Chemistry of Gold Extraction, which, by the way, he dedicated to me-at least that's what my copy says. [laughter] John, go ahead. (Message shown on Projection screen) ‘Raulerson’s Rules Plant operators and maintenance personnel should be asked to participate early in the design process. This ensures that the plant will never be completed on time or within budget.’ JOHN MARSDEN: Good afternoon, everybody. My presentation this afternoon is going to be very short. It won't be as funny as Joe Keane's, but I guarantee you it will be a lot quicker. [laughter] That transparency isn't mine, actually. [laughter] You're trying to throw me off.

Jan 1, 1998

By Ugo Preti, Gianfranco Ferrara, Mark C. Williams, Thomas P. Meloy

Theoretical and experimental lockedness profile curves are the same when the model assumptions are met. They appear different because of the way the data is presented. Continuous theoretical lockedness profile curves present all the data, including the wings of the curves giving them the deep U-shaped configuration. Experimental lockedness profile curves, because of the measurement methods, are discretized, obscuring the wings. If the continuous theoretical curves are discretized, they are similar to the experimental curves. When a float sink test is used to measure an interval of locked particles, the integrated averaging of the separation process obscures the wings of the continuous theoretical curve. To disclose the wings with experimental data, narrow density or measurement intervals must be used.

Jan 1, 1992

By Jihong Xue, Jialin Wang, Della Valle Nicola

Experience of Hard Rock TBM excavating soil in Wanjiazhai Yellow River Diversion Project tells us that selection of Hard Rock TBM to excavate soil in case that rock dominates overall length of tunnel, could be a compromise among tunneling speed, cost and quality. Risk of this operation could be greatly reduced with a detailed study of the geomechanical characteristics of the soil and, if the characteristics are suitable, money and time can be saved by using Hard Rock Double Shield TBM.

Jan 1, 2003

By Mary Fu, Helen Leung, Colin R. Phillips

In uranium mines, the median size of the aerosol has been found to be about 0.1 micron or less. Such small aerosols are readily deposited or "plated-out" on dosimeter interior surfaces resulting in the recording of a low dose. The "plate-out" properties of the CEA alpha dosimeter head are described with respect to aerosol properties in controlled experiments in the laboratory. A simple model is derived to estimate the amount of "plate-out" in the CEA head.

Jan 1, 1981

By M. Imazu, Ö. Aydan

"A new rock classification, Rock Mass Quality Rating (RMQR) proposed by the authors is briefly explained and its application for the design of tunnels and large underground openings support systems is described in this paper. RMQR is an index to evaluate the state of rock mass. The preliminary support design may be based on the concept to prevent structurally controlled failures of rock mass. RMQR can also evaluate the yielding characteristics of rock masses so that it is possible to design a support system to prevent or control the deformation of surrounding rock through the utilization of the proposed rock mass classification and some analytical and numerical techniques.INTRODUCTIONThe first three authors proposed a new rock classification system named Rock Mass Quality Rating (RMQR) (Aydan et al. 2014). RMQR quantifies the rock mass state, and using the classification system together with intrinsic geo-mechanical properties of intact rock, possible geo-mechanical properties of rock masses can be estimated. The instability modes of underground openings can be structurally controlled because of the orientation of discontinuities in rock mass and the in-situ stress induced (Aydan 1989; Aydan et al. 1993, 1996; Aydan and Genis, 2010). The authors (Aydan and Ulusay, 2013; Aydan, 2016) have also tried to apply this system to the design of a tunnel support system. The authors presented initial guidelines for the RMQR classification system earlier (Aydan and Ulusay, 2013).In this paper, the authors provide further guidelines and establish some criteria for support system design that considers loading conditions and types of underground structure according to RMQR. Guidelines are alsos proposed for selecting the proper size of rockbolts, rock anchors, shotcrete, steel ribs and concrete liner. These guidelines are based on past experiences with various underground structures, theoretical understanding and the anticipated behavior of rock mass under given in-situ stress conditions and excavation techniques. The authors also utilized some databases developed for large underground caverns and tunnels excavated in squeezing or rock-bursting ground conditions."

Jan 1, 2016

By Samir Kumar Das

Presently Geographic Information System (GIs) is gaining wider acceptance id appreciation in various resource management surveys, generation of various thematic maps, various scientific investigations, environment assessment, disaster management, etc in India but they are general in nature. A huge number of Global Positioning System (GPS) based "Total Station" are playing good roles in India for accurate and quick surveying . The GPS based real time Mine Management and Truck Dispatching System for optimization of productivity is being installed in the Panchpatmali opencast bauxite mines of India. This paper dealt in depth on GIs and GPS and their present roles in the Indian mining scenario.

Jan 1, 2002

By John C. Balla

The Spar Lake deposit is located in northwestern Montana, approximately 27 km (17 miles) south of Troy, MT, under Mt. Vernon. The deposit is a stratiform, stratabound copper-silver deposit occurring in the Revett Formation of the Proterozoic Belt Supergroup. Distribution of known sandstone-type deposits in the Revett Formation is shown in Fig. 1.

Jan 1, 1991

By Kai Nielsen

In underground mining coarse muck and large boulders lead to ineffective utilization of costly mining equipment, and extra expenses and delays caused by secondary blasting. Cost analysis in some Norwegian mines shows that these extra expenses may amount to 10% or more of total mine operating costs. A computer model has been developed for sensitivity analysis of underground longhole stope blasting. The basic idea of the model is : When increasing the blasting energy input and fragmentation costs, the fragmentation will be better. This will lead to cost savings for loading, hauling, secondary blasting and primary crushing. The blasting design giving the lowest overall costs will indicate the optimal practice. The model has been used with data from several underground operations in Norway. An example run with typical costs shows that the costs for drilling, blasting and secondary blasting are the most significant parameters in the optimization process.

Jan 1, 1986

By R. E. Wardwell, J. D. Nelson

The design of cover systems for reclamation schemes in tailings requires estimation or determination of tailings materials properties such as compressibility, shear strength, and consolidation characteristics. It is very difficult and expensive to obtain truly undisturbed tailings samples for laboratory testing. In situ testing methods have been developed for economically obtaining large amounts of information. Two of these methods are described, the piezocone and the flat plate dilatometer. Both of these methods provide a rapid means of detailed material identification in a nearly continuous fashion for the entire depth investigated. The equipment is described and typical data from a uranium tailings impoundment is presented. The results are compared and the advantages and disadvantages of these methods are discussed.

Jan 1, 1987

By Sundar S. Saluja

Efficient and re1iable methods of fragmentation through blasting have been sought ever since the introduction of black powder in mining operations, but the pace of investigation became faster with the discovery of nitroglycerine. The development of modern measuring instruments and the need to blast more rock with the least damage has made the study of blasting mechanics and its application more important, particularly since the oil embargo. Investigations into the practical approach evolved by Daws (1909) and the work done to make it more useful is discussed. The work of several investigators is touched upon with particular reference to the development of computer programs to simulate and optimize blasting operations.

Jan 1, 1986