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By R. L. Grayson

Following lip on a USBM-sponsored research project, the authors have utilized the knowledge-base structure and system concepts from the Sun Sparcstation-based worker scheduling system of the Mine Management Support System to develop a PC-based application. The new software adopts the nested-window concept to facilitate data collection and modification on personnel, their availability on a shift, and work priorities for a shift as well as to allocate manpower optimally on a work shift and delineate supervisory training responsibilities. The various components of the software are described in detail, along with enhancements made to the original system.

Jan 1, 1996

Energold Drilling Corp. is a leading specialty drilling company servicing the mineral and energy sectors in the Americas, Africa and Asia. Energold specializes in mineral exploration in remote locations with limited infrastructure. Such locations require the smallest footprint possible going in, leaving as little or no evidence on their way out. Energold?s rigs can be transported by helicopter or manually on footpaths as narrow as 1 m (3.3 ft). They set up quickly and then are struck and packed out, with any sign of their presence quickly disappearing behind them. Energold has teamed up with Atlas Copco and its team of engineers in North Bay, Ontario to design small rigs capable of drilling to a variety of depths, as required for each project.

Jan 1, 2013

By Roger D. Sharpe

Oklahoma contains extensive resources of high-purity gypsum that were deposited in the Anadarko and Hollis basins during Permian time. The gypsum resources and reserves are estimated to be about 48 billion short tons and a; located in the western portion of the state. Oklahoma is the largest producer of gypsum products in the United States. The Blaine Formation and the Cloud Chief Gypsum contain several beds of minable thickness. Four stratigraphic units in the Blaine Formation are quarried in Oklahoma. The Shimer, Nescatunga, and Medicine Lodge Members are quarried in northwest Oklahoma. The Van Vacter Member, consisting of three gypsum beds, is quarried in southwest Oklahoma. The Cloud Chief Gypsum is quarried in the west-central part of the state. The gently dipping gypsum in the Blaine Formation generally crops out along low escarpments and is covered in the downdip direction by increasing overburden, consisting of sand, shale, and/or dolomite. Anhydrite occurs in the downdip direction under the thicker overburden. The Cloud Chief Gypsum crops out as hills, which are eroded remnants of a more widespread, massive sulfate unit. All of the gypsum produced in Oklahoma is extracted using quarrying methods. A variety of products are made from gypsum quarried in Oklahoma. The products are manufactured from uncalcined, calcined, and deadburned gypsum. Products vary from raw, ground gypsum used for agriculture, to high-value-added industrial plasters, cements, and fillers produced from calcined gypsum. A sampling of the many products manufactured from Oklahoma gypsumincludes: (1) agricultural-soil amendment; carrier for insecticides, pesticides, and herbicides; calcium supplement in animal feeds; (2) gypsum wallboard-common, fire-resistant, and water-resistant varieties; (3) industrialgypsum plasters-art and casting, pottery and ceramic, molding and tooling, crayons, wall patching; (4) industrial gypsum cements-oil-well cement, high-strength statuary, high-strength tooling, fiber-reinforced architectural, road and bridge repair; (5) food and pharmaceutical-filler and binder in aspirin and other medicines, yeast activator in brewing of beer, moisture absorbent in bread and pizza dough; and (6)portland-cement retarder-ground with clinker to control setting time.

Jan 1, 1999

By J. L. Bellanca, L. R. Swanson

DISCLAIMER The findings and conclusions in this paper are those of the authors and do not necessarily represent the official position of the National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention. Mention of any company or product does not constitute endorsement by NIOSH. ABSTRACT Proximity detection systems (PDSs) for mobile machines have the potential to decrease injuries and fatalities. Early adopters of the technology have identified some challenges, which presents an opportunity to explore and improve the integration of mobile PDSs in underground coal mines. The current study applied the task-technology fit framework to investigate the fit between mobile PDS technology and mining relative to health and safety, from the perspective of leaders at two coal mines. Quantitative results from the study show that mine leaders evaluated mobile PDS favorably for training and ease of use, system feedback, user authorization and experience, and less favorably for safety, compatibility, task completion, and reliability. Qualitative results reveal specific task, mine, and system characteristics that may have influenced leaders' evaluations. The study includes considerations for safe technology integration. INTRODUCTION Striking, pinning, and crushing accidents related to mobile machines continue to be a major concern in underground coal mining. The National Institute for Occupational Safety and Health (NIOSH) linked 22 of the 75 underground mine fatalities reported between 2011 and 2015 to power haulage [1]. The Mine Safety and Health Administration (MSHA) asserts that proximity detection systems for mobile machines (mobile PDSs) could help to prevent these types of fatal injuries [2]. Mobile PDSs use a collision avoidance technology that allows the mine to establish hazard zones and employ electromagnetic sensors to detect workers equipped with a miner-wearable component (MWC) working near these mining machines. The authors characterize a mobile PDS as an automated technology, because—in line with Lee & See’s [3] definition of automation—a mobile PDS actively “selects data, transforms information, makes decisions, or controls processes” (p. 50). When the system detects workers in the established hazard zones, it issues alerts and slows or stops the mobile machine. Even though a mobile PDS may be a viable and promising safety solution, there are still a number of questions regarding how well this automated technology will fit with mining tasks and conditions. Using a mixed-methods approach, the current study explored factors that influence the fit of mobile PDSs in the underground mining environment.

Jan 1, 2019

By Vince Saporito

Miners work in dangerous terrain, around the clock, with heavy equipment. Is there room for improvement in safety and standardization in the mining industry? Recent history would suggest there is a need for action. At a 2011 Spring Thaw conference in Denver CO, one speaker commented, ?We are having a number of incidents with workers getting ?pulled? into rollers or ?trapped? at transfer points when trying to manually clean (it) while the conveyor is still in motion.? It?s a troubling thought. These actions are specifically prohibited under U.S. Mine Safety and Health Administration (MSHA) regulation 57.14202. Another official from MSHA earlier this year indicated with today?s technology and policies presently in place, ?we should not be repeating the same incidents and violations year after year as we currently do.? But we are doing exactly that.

Jan 1, 2012

By M. Karmis

The algorithms for the mathematical modeling to predict productivity of underground room-and-pillar mining systems are well known and documented. These algorithms consider the time-varying relationships between mining equipment for a given geometry of operations as well as other constraints. This paper presents WebConSim, a newly developed, Web-based, user-friendly computer simulation tool for the Windows environment. The simulator is easily customized for use by field engineers, planning engineers, and management and will help mine operators plan the optimum mining sequence for different mine geometries and equipment layouts. Program output includes production data and equipment utilization indices, as well as time driven event chains that can be used for virtual reality presentations.

Jan 1, 2001

The 29th annual American Mining Hall of Fame Awards Banquet and Fundraiser sponsored by the Mining Foundation of the Southwest (MFSW) will be held at the JW Marriott Star Pass Resort, Tucson, AZ on Saturday, Dec. 3, 2011. Each year, one living inductee, two recipients of Medals of Merit, and up to five honorees from mining history are chosen by the MFSW for their outstanding contributions to the mining industry. Chilean Minister of Public Works and former Minister of Mining, Laurence Golborne Riveros will be the guest of honor, featured speaker and inductee into the American Mining Hall of Fame. Golborne Riveros was instrumental in managing the rescue of the 33 Chilean miners in October 2010 and in the coordination/management of the ?townsite? for family members, rescue support and the media. His engineering background and executive management skills made him ideally suited to assist in both a technical and managerial role in this emergency.

Jan 1, 2011

By Juan J. Monsalve, Mario Karfakis, AMAN SONI, Nino Ripepi, Jim Hazzard

Pillar collapses are events that due to their severe consequences can be classified as high risk. The design of pillars in underground room-and-pillar operations should migrate to risk-based design approaches. The authors of this work proposed a risk-based pillar design methodology that integrates stochastic discrete element modeling for pillar strength estimation, and stochastic finite volume modeling (FVM) for stress estimation. This paper focuses on the stochastic FVM component for stress estimation. The mining and geomechanical aspects of a case study mine (CSM) are described and pillar stresses are estimated by using three approaches: (1) analytical solutions, (2) 2D finite element modeling, and (3) 3D finite volume modeling. This operation extracts a 30° dipping deposit, which makes current underground stone mine design guidelines inapplicable for this CSM. This work compares results from each stress estimation approach and discusses uses the point estimate method as a simplified stochastic approach to evaluate the effect of rock mass elastic properties variability on pillar stress distribution. Results from this work show that the three estimation approaches lead to different estimations, possibly, due to the wide range of assumptions each estimation approach considers. It was also determined that the horizontal to vertical stress ratio has a significant impact on pillar stress magnitude. Therefore, it is recommended to perform in situ stress measurements, or assume worst-case-scenario values to account and reduce uncertainty due to this parameter. The stochastic stress estimation approach used in this paper provides results that can integrate a risk-based pillar design framework.

Sep 24, 2022

By Fred Pena

Cyprus Pima Mining Company is located in the Mineral Hill District of southern Arizona, approximately 22 miles south-southeast of Tucson. Cyprus Pima Mining Company is owned 50.01% by Cyprus Mines Corporation, 24.99% by Utah International Incorporated, and 25% by Union Oil Company of California, with Cyprus having the management responsibility. Cyprus Pima's history has been one of continued expansion from an initial plant of 3,000 TPD in 1957; 6,000 TPD in 1963; 18,000 TPD in 1966; 36,000 TPD in 1967; and 53,500 TPD in 1972. The major reason for Expansion IV was that a large volume of low-grade ore had to be moved to get at a higher grade ore in the course of proper pit development. With mining costs already defrayed, this relatively hard, low-grade material became economically profitable for subsequent milling and concentrating treatment. Similar material previously stockpiled was available for ore treatment. In an effort to meet the continuing search for lower unit costs, the largest milling and concentrating equipment had to be examined. The management of Cyprus Pima Mining Company began investigating autogenous, and semi-autogenous milling in 1964 when two carloads of ore selected from the Cyprus Pima pit were sent to the Koppers--Hardinge Operation at York, Pennsylvania for testing. One car contained approximately 40 tons of hard arkosite and the other contained approximately 40 tons of ore classified as soft Hornfels. The purpose of the testing was to determine the amenability of both ore types to autogenous or semi-autogenous grinding.

Jan 1, 1974

By Josh Swank

Albert Einstein once said, ?the important thing is not to stop questioning.? In the mining industry, a lack of inquisitiveness may lead to a blissful ignorance but it certainly will not increase efficiencies. While one may claim necessity is the mother of invention, questioning and analyzing how methods and systems can be improved is the catalyst to discovering necessities. Understandably, when working in the middle of Canada?s oil sands, where trucks operate around the clock every day of the year, it is nearly impossible to pull the nose from the grindstone long enough to provide thorough analysis. But, fortunately, some manufacturers/inventors have assisted by examining the process and the ensuing headaches within this application.

Jan 1, 2013

By R. J. Hickson

The Grasberg copper-gold deposit was discovered in Spring 1988, just one year prior to the planned closure of Freeport Indonesia's original Ertsberg open pit copper mine. In spite of Grasberg's remote location, 600m above the Ertsberg, atop a hitherto inaccessible mountain, Freeport-McMoRan brought their latest open pit mine into production in the last week of 1989, less than two years after discovery. This paper describes the start-up of the operation, highlighting synergies drawn from both the original Ertsberg experiences and the current Freeport Indonesia underground mines.

Jan 1, 1991

By James Paone

Drillability of rocks by mechanical means is closely related to the physical properties of the respective rocks, Various approaches by previous investigators on rock drillability are presented, as well as recent techniques studied by the Bureau of Mines. The studies show drillability concepts based on (1) theoretical drilling equations derived from laboratory drilling experiments extended to field drilling results and on (2) a statistical method where multiple regression analysis is used to develop a prediction equation for drillability.

Jan 1, 1966

By R. T. Langland

The U.S. Bureau of Mines has conducted underground tests and computer analyses to study coal mine roof behavior. Southern Ohio Coal Company provided test sites it) their Heigs mines located near Athens, Ohio. Testing apparatus was adapted for monitoring roof behavior at the face of mining from a remote surface location. Finite element analyses were applied to study the structural conditions present. Test sites were located at three different intersections of entries and crosscuts of the room-and-pillar mine. Electrical read-out instruments were used to record roof bolt loads, roof sag, and roof-floor convergence. They were installed during the roof bolting cycle of a conventional mining section and data was recorded for several months. Normal mining operations continued throughout the test period with minimal interruptions due to the installation and monitoring of the instruments. A computerized data acquisition system, partly underground, partly on surface, permitted continuous monitoring of data and its retrieval, display, manipulation, and storage. The finite element code used to model the test sites accounted for three-dimensional geometry, nonlinear material behavior, and the mining excavation and bolt installation sequences. Results of the test are highly variable. Comparable values between test and analysis results were obtained by applying statistical averaging of. roof test data. Results of the analyses indicate that bolts have a lesser effect on the gross behavior of mine roofs than has been indicated and that bolt load changes are strongly influenced by mining excavation sequence, bolt-placement sequence, and face distance

Jan 1, 1977

By David I. Smith, Kenneth Arnold, Bryan Aweh, Vincent Falkowsk, Brian Lakin, Andy Fer

Nassau County, New York, is undertaking several projects to improve the water quality in the Western Bays of Long Island. A major step forward will be the completion of the Bay Park Conveyance Project, which will divert most treated effluent away from the Western Bays to an existing ocean outfall at the Cedar Creek Water Pollution Control Plant. The ongoing works include 3.6 miles of microtunneling, 7 miles of sliplining, 14 shafts, and a 75 MGD pump station. This paper provides an overview of the design and an update on construction progress through December 2022. The project is a collaborative effort between Nassau County, New York State Department of Environmental Conservation, the design-builder, and various consultants.

Jun 13, 2023

By Eric Jacobs

"Building and operating tunnels has been a highstakes endeavor in terms of costs, complexity, safety and impact on contractors, owners and the public for a long time. There are many variables that need to be closely monitored and managed to construct a tunnel on-time, on-budget and safely. Once built, there are also many elements that need to be monitored and managed to operate a tunnel safely and efficiently.Fundamentally, the risks to the safe and efficient construction and operation of a tunnel are a function of the degree of harm and the likelihood of the harm occurring. From a cyber security perspective, risk assessments used to inform decision makers and support risk responses are typically based on identification of relevant threats; internal and external vulnerabilities; the impact that may occur given the potential for threats to exploit vulnerabilities and the likelihood that harm will occur. This article focuses on creating awareness of vulnerabilities associated with technology used in tunnel construction and operation and some of the challenges associated with remediation of these vulnerabilities. As we all know, technology has been evolving at an accelerating pace and infiltrating every aspect of our lives in new and often exciting ways. In the world of tunneling, sensors and systems that provide position and time have become accurate, rugged and cost-effective enough to come out of the research labs and into the equipment and systems used every day. There are many opportunities to employ connected computing devices and sensors to costeffectively capture, integrate and analyze key data with minimal latency to manage risk better, improve safety and avoid surprises."

Jun 1, 2019

By Brianna M. Eiter, Jennica L. Bellanca

Mineworkers face a challenging and dynamic work environment every workday. To maintain a safe workplace, mineworkers must be able to recognize worksite hazards while they perform their jobs. Though hazard recognition is a critical skill, recent research from the National Institute for Occupational Safety and Health (NIOSH) indicates that mineworkers fail to identify a significant number of hazards. To further the understanding of mineworkers’ hazard recognition ability and to begin to address hazard recognition performance, NIOSH researchers analyzed data collected during a laboratory research study to determine the effect of individual mineworker factors including risk attitude, work experience, and safety training on hazard recognition accuracy. The results of this study show that mineworker risk attitude and safety-specific work experience affect hazard recognition performance while hazard-specific safety training does not. These results suggest that some of these individual factors can be overcome through experience and training. Potential strategies that can be used to address these factors are also discussed.

Aug 31, 2020

By M. R. Shahan, C. E. Seaman, S. E. Mischler, T. W. Beck

"Float dust deposits in coal mine return airways pose a risk in the event of a methane ignition. Controlling airborne dust prior to deposition in the return would make current rock dusting practices more effective and reduce risks of coal dust-fueled explosions. The goal of this NIOSH study is to determine the potential of open-air water sprays to reduce concentrations of airborne float coal dust (<75 µm diameter) in longwall face airstreams. This study evaluated unconfined water sprays in a featureless tunnel ventilated at a typical longwall face velocity. Experiments were conducted for two nozzle orientations and two water pressures for hollow cone, full cone, flat fan, air atomizing, and hydraulic atomizing spray nozzles. Gravimetric samples show that airborne float dust removal efficiencies averaged 19.6 percent for all sprays under all conditions. The results indicate that the preferred spray nozzle is operated at high fluid pressures to produce smaller droplets and move more air. These findings can be used to select sprays and design spray arrays to control airborne float dust over the entire longwall ventilated opening. INTRODUCTION Coal mining processes produce airborne dust that naturally deposits on the floor, roof, and ribs of mine airways. These fine dust particles, termed float coal dust when smaller than 75 microns in diameter, are deposited in return entries of coal mines and can be re-entrained by pressure waves induced by methane-air explosions (Rice et al., 1911; Nagy, 1981; NIOSH, 2006). These particles are also those most likely to participate in coal dust-fueled explosions, which can potentiate and propagate explosions resulting in extensive damage. In order to meet compliance requirements of at least 80 percent incombustible content in the composition of material deposited in mine entries (CFR, 2016), coal mines apply an inerting agent, specifically, rock dust (Harris et al., 2009). Should methane be present in the mine atmosphere, the required fraction of incombustible content is further increased by 0.4 percent for each 0.1 percent methane. The removal of airborne float coal dust (AFCD) prior to deposition is an approach intended to make current rock dusting practices more effective by increasing the proportion of inert material to combustible material, resulting in a lower risk of coal dust-fueled explosions. Water sprays are both effective and widely accepted as a method for controlling underground coal mine dust. In fact, water sprays are considered to be the most economical and technically feasible means of reducing dust concentrations in underground coal mines (Courtney and Cheng, 1977; Barker and Humphreys, 1996). Sprays are used in several ways to control dust in mining processes: inhibiting dust formation, immobilizing dust to prevent it from becoming airborne, and capturing airborne dust (Cheng, 1973). Reductions in airborne dust concentrations have frequently been attributed to inertial impaction between water droplets and dust particles, forming larger agglomerates which then quickly precipitate out of the airstream (McPherson, 1993). Inertial impaction activity is generally accepted as the major capture mechanism for airborne particles larger than 0.5 µm in diameter. It is this mechanism that is evaluated in this study."

Jan 1, 2017

By Joseph P. Nugent

The new combination gypsum plaster and gypsum wallboard plant of Compania Industrial Kaiser S.A., the first of its kind in Mexico went into production in April of 1969. This was approximately fourteen months from the signing of the formal order for the plant and equipment. Compania Industrial Kaiser S.A. is an affiliate of the Kaiser Gypsum Company in the United States and will market practically the same line of products and to the same standards as those produced in American plants. Located in the City of Puebla, the plant will readily service the major Mexican sales areas. It is approximately 85 miles away from Mexico City on a modern, four-lane, divided highway and distribution to other major consumer areas can be readily effected by the use of a good highway system, as well as, by rail. This, plant is the, sixteenth Gypsum Wallboard Mill supplied abroad by my company, United States Wallboard Machinery Company. Other installations are in Australia, New Zealand, Chile, England, Scotland, Ireland, Finland, South Africa, Latvia and Germany. Two new mills are on order; a small unit for Brazil and a comparatively large unit for New Zealand. All these mills have one thing in common with plants in the United States and Canada; they are equipped with standard, time-proven and tested equipment and they are designed in accor¬dance with the latest engineering thinking in order to produce efficiently, the highest quality product at lowest cost. They differ generally in the size of plant, the factors that brought them into being and in the market that they supply. I believe that these differences will be of interest to you.

Jan 1, 1969

By L. L. Chasko, D. W. Alexander

Researchers from the National Institute for Occupational Safety and Health’s Office of Mine Safety and Health Research conducted an assessment of the effects that ground control mesh might have on rock and float coal dust distribution in a coal mine. The increased use of mesh to control roof and rib spall introduces additional elevated surfaces on which rock or coal dust can collect. It is possible to increase the potential for dust explosion propagation if any float coal dust is not adequately inerted. In addition, the mesh may interfere with the collection of representative dust samples when using the pan-and-brush sampling method developed by the U.S. Bureau of Mines and used by the Mine Safety and Health Administration for band sampling. This study estimates the additional coal or rock dust that could accumulate on mesh and develops a means to collect representative dust samples from meshed entries.

Jan 1, 2014

By L. L. Chasko, D. W. Alexander

Los investigadores del National Institute for Occupational Safety and Health’s Office of Mine Safety and Health Research han evaluado los efectos que la malla de control de suelos podría tener en la distribución de polvo flotante de roca y carbón en minas de carbón. El creciente uso de mallas para controlar el desconchado o caída de material del techo y las vigas introduce superficies elevadas adicionales para recolectar el polvo de roca o de carbón. Es posible que el potencial para la propagación de explosión del polvo se incremente si el polvo flotante de carbón no es convertido en inerte de manera adecuada. Adicionalmente, la malla podría interferir con la recolección de muestras representativas de polvo cuando se usa el método de recipiente y brocha desarrollado por la U.S. Bureau of Mines y usada por la Mine Safety and Health Administration para muestreo de banda. Este estudia hace una estimación del polvo de roca o carbón adicional que pudiera acumularse en la malla y desarrolla un método para recolectar muestras de polvo representativas atrapado en las mallas.

Jan 1, 2014