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By R. Y. Wan, J. D. Miller, P. L. Sibrell

Three different refractory carbonaceous gold ores from the Carlin operation in northeastern Nevada were investigated to characterize the effect of passivation treatments on the nature of the carbonaceous material. The carbonaceous material was chemically isolated from the ores and passivated residues, and examined by FTIR spectroscopy, elemental analysis, and gold adsorption capacity. The main component of the carbonaceous material in these ores was found to be a naturally occurring activated carbon-type compound. Hydro-carbons were detected on rare occasions, but no evidence was seen for humic acids. Ore samples were passivated by autoclaving, or by treatment with sodium hypochlorite or gaseous chlorine. In some of the passivation tests, a new peak was observed in the IR spectra of the isolated carbonaceous material, that was due to carbonyl functionalities. However, all of the passivation treatments tested decreased preg robbing significantly. This suggested that the appearance of the carbonyl peak was due to the severity of the conditions during passivation, rather than the method used.

Jan 1, 1990

By J. P. A. Hortley

In conventional electrolytic copper production, looped copper starter sheets, on which the copper is deposited, are supported by hard-drawn copper bars. These bars have cross-sectional areas of between 1 and 1.4 in2. The suspension bars serve two purposes: firstly to support the cathode, which can weigh up to 150 kg, and secondly to introduce the electric current. IYI examined these two requirements in detail to see whether a better design could be achieved. Considering firstly the current carrying requirement, it wee noted that under normal refinery conditions, each cathode carries between 400 and soak. If one applies the generally accepted rule that 1 in of copper can carry 1000A4 a suspension bar need theoretically contain only 1/2 in2 of copper. This contention is supported by the fact that the 500A current passed through the cathode also appears to pass quite satisfactorily through the two support loops, which have a cross-sectional area of approximately 0.35 in 2. Turning now to the strength requirements, the cross-section of hard-drawn copper bar required to support a 150 kg cathode is relatively small, and easily met by the present designs. It is not, however, the static load applied by the 150 kg cathode immersed in the electrolyte which causes the damage to the hard-drawn copper, or even the increased static load of a 100 kg man standing on one foot in the centre of the bar; the damage is actually caused by the dynamic loads applied to the bare when they are dropped, thrown into containers, lowered too rapidly into the cell, or otherwise mistreated. The important requirement is therefore that the bar does not permanently bend. Its proof stress of limit of proportionality, rather than the amount that it deflects under static loading, should be the strength criterion. With the hard-drawn copper normally used for the manufacture of suspension bars, it has been observed that the copper becomes annealed during use, particularly at the end of the bar where the current is introduced. Thus, after a relatively short time, the cathodes are in effect being supported by annealed copper bars.

Jan 1, 1978

By A. T. Yu

As a nation, we have been known as perhaps the most wasteful in history. From the perspective of engineers and builders on the other hand, planned obsolescence and demolition did beneficially pave way for growth and provided environment for new businesses. Recent economic recession and intense competition from overseas, however, have drastically changed the economics. The high cost of capital and the demise of indiscriminate plant expansion have totally altered the way we conduct our business and run our operations. As a response to increasing demands for better efficiency with little or no funding available, everyone is forced to make do and do better with whatever little he has. Today it nay not be an exaggeration to state that modification of existing facilities may have finally emerged as a way of life. This paper will outline examples of how several companies have effectively modified existing facilities to do more and do it efficiently without having to demolish everything and/or to spend a fortune.

Jan 1, 1985

By C. I. Wilmot, A. Sass, J. VanDeBeuken

Introduction This chapter addresses the need for operation manuals, presents an outline as a guide for writing the manual, discusses who should write the manual, suggests how it is implemented and gives tips to potential manual writers. Theory & Purpose of Operating Manuals The primary objective of the operating manual is to provide every operator the benefit of a uniform minimum level of training. This training is not only critical to the safety and efficiency of every employee, but also provides a basis for incorporating future operational improvements into standard and emergency procedures. The manual promotes safety through- out and additionally has a special section devoted to safety. The operator should be able to find information on chemical and physical hazards as well as be exposed to safety procedures for such items as motor lockouts and tank entries. The operating manual will usually reference a separate safety manual or incorporate parts of the safety manual. Safety is also promoted through standardized procedures for operation of equipment. Standardized operation is the second most important reason for the writing of manuals. If equipment is started, operated, and shut down in a consistent manner, then operational efficiency should be maximized. If it is not, then the procedure is adjusted until it is. The experience of many can be condensed into set responses for start up, shutdown, steady state operations, and upsets. Implicit with the standardized operation objective is a minimum level of training the operator will receive by thorough familiarization with the manual. The ability to know the contents of the manual is a basic requirement for operator status. The operating manual serves as a basis for a training program both at the start of the new plant and as new operators are hired or promoted into the job. The operating manual is a collection of at least part of the knowledge that "key people" own and will cushion the loss of key personnel for whatever reason. The manual can only fulfill these lofty goals by being a dynamic document. Manuals must change as equipment is modified and superior techniques evolve. To be effective they must be periodically updated, so word processors and reproduction

Jan 1, 1986

By Howard L. Hartman

Introduction The federal government's declining role in funding research has created a critical dollar gap for university departments of mining engineering. Industry, too, is affected by the drought. Research is lagging. Hardpressed universities are going to the private sector for funding. Mining companies should not shower universities with philanthropy, but a research partnership should be contracted on a pay-as-you-go basis. A model exists at The University of Alabama (albeit not in mining) that could be adopted by the mining industry. An equal partnership arrangement between a university and an industry for conducting research is proposed. The concept is not that a corporation sponsors and a university performs the research. Nor does it call for educational contributions or giveaways from industry. Rather, the corporation and the educational institution enter into a cooperative research endeavor, a full and equal partnership. Both parties contribute and both share the benefits. A key to the relationship is that it has a single objective: it must generate profits or reduce costs for the company. Working Model Recent literature is replete with examples of proposals for joint research endeavors, involving both contracts and grants, between industry and universities (Bronwell, 1971; Bugliarello, 1978; Branscomb, 1981; Sanford and Holland, 1982). They are all good proposals and offer something to both parties. They are, however, not widely supported. Few have received a favorable nod from the US mining industry. Though it may be logical, for example, to remake the American Mining Congress (or some new consortium) in the mold of umbrella-type industry organizations to fund cooperative research with mining institutions, such proposals have never flown. What model, then, will work? First, look for a model that has worked in industry in general. Second, seek to apply it to mining specifically. There is a model project that satisfies the first of those criteria. It is a project complicated by a third party, in addition to a corporation and a university. In January 1983, the "Factory of the Future Project" was initiated between The University of Alabama (UA) and General Motors Corp. (GM). The United Auto Workers (UAW) is a third party to the agreement. The factory was GM's Rochester Products Division manufacturing plant in Tuscaloosa, AL, also home of UA's main campus (Fig. 1). Saving a Plant The agreement came about at the initiative of GM and the UAW. Faced with having to close the plant because of excessive production costs, company and union officials proposed to the university that an applied research facility be established at the plant. The university would operate the laboratory, dedicated to $470,000 a year cost reductions for the company. The school would lease the 5.1 km2 (55,000 sq ft) space for $470,000 a year for three years. Any savings effected by the university's research effort would be credited toward to the rent. GM said the small factory, which made replacement carburetors

Jan 9, 1984

By Svante Lundbrink

A new generation hydraulic rock drill featuring more than 50 percent higher performance than other drills has been introduced by Atlas Copco. In conjunction with the new rock drill, control systems have developed and refined to handle the higher drilling output, and to maintain an acceptable service life of drill string components. These improved features are built into the Rocket Boomer, a new high-performance drill rig, used at the recently completed Hanging Lake project in Colorado. Experiences from this project will be reported together with results from a highway tunnel construction project in Italy.

Jan 1, 1991

By Eleanora I. Robbins, Motoaki Sato

Many problems associated with acid mine drainage (AMD) are caused by the complex way molecular oxygen (O2) oxidizes reduced matter at surface temperatures. In aqueous solution, O2 kinetically "prefers" to go through the formation of hydrogen peroxide (H2O2) as an intermediate. Being innately unstable, H2O2 is quickly decomposed back to water and oxygen in the presence of dissolved Fe and Mn, both catalysts for the decomposition. Direct addition of H2O2 to AMD produced similar results. Ozone (O3) is a much faster and stronger oxidizer than either O2 or H2O2. In the laboratory, O3 rapidly precipitated Mn, Fe, Ni, Co, Pb, and Ag even in acidic solutions. The experiments indicate that AMD can probably be processed with ozone and metal oxides/hydroxide recovered in flow systems using only septic-tank-size reactors and small sedimentation ponds.

Jan 1, 2000

By Connor Meinke, Shaihroz Khan, Kevin Erwin, Rajiv Chandramohan, Muhammad Usman Siddiqui

A geometallurgy study aims to link metallurgy and geology to reduce technical risk and enhance the economic performance of a mineral-processing plant. It does so by accounting for variability in a deposit to develop cash-flow models with variable throughput rates. High-quality sample selection for metallurgical test work that is representative of the deposit is an essential component of a geometallurgy study, but the large multidimensional data set makes sample selection a daunting task, as classifying the data set while respecting its heterogeneity is difficult. This paper presents a streamlined approach for sample selection, using statistical analysis techniques in Python. It cuts down time to select samples from around 1,200 s per drillhole to about 60 s for data classification and from 12 h to 8 h for handpicking samples from the classified data set, translating to cost savings. The cumulative sum method and k-means clustering method are used in the methodology to elegantly classify the data and select representative samples. The effectiveness of the methodology is demonstrated by presenting data from a prefeasibility study of a copper-iron mine in which 40 samples were selected for flotation test work.

Dec 1, 2024

By Richard R. Radel, Jack Barry

Contract required excavating 2,000 If of 14' horseshoe tunnel in rock, a 95' deep work shaft on shore, and a 50' deep intake shaft located in the middle of the Niagara River just above Niagara Falls. Large quantities of H2S were encountered in the range of 20 PPM with ventilation. Peak levels of 40 PPM were recorded. The original designed ventilation system required only a volume of 10,000 CFM to meet OSHA requirements. The volume of air was increased to 50,000 CFM to dilute the H2S to al- low workmen to work and comply with OSHA H2S action levels. The second phase of the tunnel consisted of placing 72" ID X 20 foot long concrete reinforced pipe in the tunnel. When the tunnel was holed through and both shafts were open, a substantial amount of work was required to take place in the shafts which eliminated the possibility of placing a bulkhead to secure proper ventilation. The ventilation team designed a jet system airlock. The design of this system was to bring fresh air down the work shaft in two duct systems; one 30" diameter and one 24" diameter. Following the excellent work of Jan Wolski (7th Mine Ventilation Symposium chapter 58) our design incorporated nozzles located approximately 100' in by the work shaft. The velocity of the 24" diameter duct was 6,365 FPMD2.2 MPH. The velocity of the 30" diameter duct was 6,117 FPMl69.5 MPH. Both systems were on blow and being that air expands at 3112 degrees per side this high velocity of air expanded and created an air bulk head through which men and the large sections of concrete pipe could be passed without any delay or additional cost to the project.

Jan 1, 1997

By S. Nunoo

The shape of particles has a significant effect on the shear strength and deformational characteristics of granular materials. Weathering can change the grain shapes. For example, more weathered sands tend to be rounder regardless of particle size. Particle shape analysis was performed on samples collected from the Questa mine rock piles, a debris flow and the pit alteration scar. In order to increase the validity of the particle shape analysis, 4 persons including 2 geologists and 2 mining engineers were involved in describing the particle shapes. The results of this analysis indicate that rock fragments in the collected samples are mainly subangular, subdiscoidal and subprismoidal. The sphericity and angularity of the rock fragments of the older analogs are similar to those of the rock piles. This suggests that short-term weathering (<100 years) has not noticeably changed the particle shapes at the test locations. Rock piles made of more angular particles are more stable compared to rock piles with rounded particles.

Jan 1, 2009

By C. Bemelmans

Lead alloys function effectively as oxygen evolving anodes in copper SX-EW operations and are highly resistant to corrosion. The presence of organic from solvent extraction in the electrolyte seemed to enhance solution line attack. Laboratory tests showed that lead is soluble in D2EHPA, Acorga and LIX 984 to a limited, yet measurable degree. Lead alloys and various lead phases formed on the anode were tested to evaluate their effect on the corrosion process in organic media. Possible causes for anode corrosion and mechanisms responsible for their initiation will be discussed.

Jan 1, 1996

By John C. Stam

During the past 20 years, the seismic refraction method has been used for depth to bedrock investigations. Its usefulness, however, has been recognized mainly in engineering applications, for instance in connection with the construction of power stations and in dam site investigations etc. Although some knowledge of the depth to bedrock can be of advantage in many other fields, the use of the conventional 12 or 24 channel seismic refraction equipment has been very limited, especially in ore prospecting and mining operations. The reasons for this are mainly the rather complicated operation of the instruments and the high costs. A conventional seismic equipment requires a crew of six men, a highly trained operator and an interpreter. Furthermore, the use of explosives can under certain conditions be undesirable (naighbourhood of houses, damage to agricultural areas etc.). Since 1957 a new one-channel seismograph, &apos;constructed by Geophysical Specialties Company, Minneapolis, Minnesota, has been in use and this instrument simplifies operations and reduces their costs considerably.

Jan 1, 1959

By John C. Balla

The Troy deposit is located in northwestern Montana, approximately 17 mi south of Troy. The deposit is a stratiform, strata- bound, copper-silver deposit which occurs in the Revett formation of the Proterozoic Belt Supergroup. The Revett formation is approximately 1730 ft thick in the vicinity of the Troy deposit, and is divisible into three units. The upper Revett, approximately 250 ft thick, is the host for the orebody. The Revett represents a deltaic environment. The Troy deposit was discovered by Bear Creek Mining Company in 1 963 during the course of a reconnaissance stream sediment sampling program that was designed to discover strata-bound copper deposits. The deposit is approximately 7500 ft long, 1800 ft wide, and averages 60 ft thick. It is bounded on the north by outcrop, on the east by a post-mineral fault, on the south by diminishing grade and post-mineral faults, and on the west by diminishing grade. Ore reserves are 64 million tons with a grade of 0.76% Cu and 1.58 oz Ag per ton. The mine is presently operating at a production rate of 4.2 million oz of silver and 20,000 tons of copper per year.

Jan 1, 2013

By Fabio Amaya, Andrés Marulanda, Ramiro Gutiérrez, Alberto Marulanda

The behavior of a salt rock mass is strongly related to a creep phenomenon. The amount of creep depends on the level of stress generated in the underground excavation. Additionally, security conditions and the lifespan of an underground cavern excavated under this geological conditions depend on the evolution of creep. Based on the experience of the failure of the Old Underground Salt Cathedral of Zipaquirá(Colombia) and the construction of the new one, the theoretical framework to predict the creep behavior of a salt rock mass is explained. The theoretical formulations are calibrated based on actual observations of the material behavior to predict the lifespan of this striking structure.

Jan 1, 2003

By Frank G. Horino, V. E. Hooker

INTRODUCTION The determination and use of mechanical properties of rock in engineering and rock mechanics are rapidly developing. Many of these properties are determined on intact rock specimens; thus, their application and repre¬sentation of rock mass properties may be limited. How¬ever, relative information often provides useful guidance in the solution to mine design and stability problems. Summarized in this chapter are some of the stan¬dardized techniques and procedures currently used to obtain these mechanical properties. Typical applications of the use of these properties are also presented. Stan¬dardized techniques include those advanced by the American Society of Testing and Materials (ASTM), International Society of Rock Mechanics (ISRM), US Bureau of Mines (USBM), Canadian Dept. of Mines and Technical Surveys, South African Institute of Min¬ing and Metallurgy, and other individual investigators. Information on the mechanical properties of rock and the behavior of the rock under a given system of stresses represents a necessary part of the information for rational engineering design for any given mining op¬eration. The mining method, the type and extent of sup¬port, the extraction ratio, the overall dimensions of the mine, and the orientation of the rooms and pillars are all decisions that are influenced by the mechanical prop¬erties of the ore, roof, and floor material under various stress systems and the magnitude and direction of the in situ stresses (Hooker, Bickel, and Aggson, 1972). Initial mechanical property information regarding a structure or mine property is generally obtained by two basic techniques: (1) static and dynamic property tests are conducted on intact and fractured rock specimens of exploratory drill core, and (2) dynamic properties are obtained by borehole logging techniques. When mining access becomes available, and as the mining horizon is expanded, additional information can be ob¬tained to verify preliminary mine design values. This chapter presents some of the standardized tech¬niques and equipment currently used in obtaining me¬chanical property data in the laboratory. The properties considered are: (1) uniaxial compressive strength of intact rock core specimens, (2) uniaxial compressive strength of rock cores containing planes of weakness, (3) triaxial compressive strength of intact rock core specimens, (4) triaxial compressive strength of cores with a plane of weakness, (5) Young&apos;s modulus, (6) Poisson&apos;s ratio, (7) density or apparent specific gravity, (8) modulus of rupture, (9) indirect tensile strength, and (10) creep characteristics. Where possible, an at¬tempt will be made to evaluate each property measure¬ment in relation to the problems of rock mechanics and application of results. TEST SPECIMENS The selection and care of drill core for laboratory testing require some consideration. It is recognized that laboratory-determined properties are not necessarily rep¬resentative of an in situ rock mass property. However, relative information between beds or zones of interest is still valuable information in selecting mining horizons and preliminary design criteria. To provide statistical data the number of drill core samples selected to repre¬sent each of the areas of interest should be from a mini¬mum of three to a maximum of ten test specimens. A judgment must also be made on site as to whether the recovered drill core should be wrapped and sealed in plastic to preserve moisture. On the one hand investiga¬tions of air-dried and saturated specimens have shown that moisture significantly affects the elastic properties and strengths of many rock materials (Obert, Windes, and Duvall, 1946; Colback and Wiid, 1965); on the other hand it is apparent that most core drilling is done with water which may saturate the specimen to a greater extent than in the in-situ condition. Whether or not the decision is made to retain the moisture, the core should be delivered to the laboratory as soon as possible after recovery for subsequent specimen preparation and testing. Specifications Shape: The shape of the specimens influences lab¬oratory testing in two ways: (1) time and cost of sam¬ple preparation and (2) strength of the material. Cy¬lindrical specimens of drill core are by far the least time-consuming to prepare for static or dynamic labora¬tory testing. In addition, the cylindrical shape lends it¬self to a more uniform stress distribution throughout the sample than other shapes, such as rectangles and hexa¬gons. The compressive strengths of various shapes have been studied (Grosvenor, 1963, and Price, 1960), and results indicate that the cylindrical specimens usually provide the highest strength for a given height-diameter ratio. However, reduction in strength from a cylindrical shape to a rectangular in situ pillar is not regarded as significant in relation to other considerations such as planes of weakness in a pillar or safety factors in the design process. Length-Diameter Ratio: The length-to-diameter ra¬tio, LID, has a significant effect on the compressive strength. Various recommendations have been made to use standard LID ratios ranging from 2 to 2.5 to 3 (ASTM, 1975c; ISRM, 1972). However, past work by others such as Obert, Windes, and Duvall (1946) has shown that excellent results can be obtained using LID ratios from 2 > (LID) > >/s. In selecting an LID ratio for testing, one should keep in mind the amount of material available for testing. In many instances, this may be limited. Thus, a shorter specimen such as 1: 1 LID may be necessary to provide enough test data for statistical analysis of results. Sec¬ond, it may be desirable to obtain elastic constants dur¬ing the test. This generally requires instrumentation such as linear variable differential transformers (LVDTs) or strain gages near the center of the specimen. In this case, an LID of 2.5 or 3 is desirable so that the instru

Jan 1, 1982

By C. J. Bise

Virtual reality (VR) is a concept in which the human experience of perceiving and interacting with a computer-modeled environment is achieved through the use of sensors and effectors. It is an advanced form of computer graphics. The images are generated based on where the user looks and how the user moves. As personal-computer-based (PC) instruction gains acceptance as an innovative approach to providing safety training, VR can provide a multisensory, rather than merely a multimedia, mode of presentation. New technology continues to be introduced into the mining industry to meet the productivity needs of coal and noncoal producers. There is also an increased need for more innovative training of mine workers. New technology and equipment designs often affect the basic causes of accidents. For example, the development of cabs and canopies for underground coal-mine equipment has reduced the number of accidents related to roof falls and rib rolls. However, safety-training specialists then had to focus on the machines themselves, because the modifications had the potential for causing "pinch-point" accidents. In fact, although the overall physical demands on mine workers have diminished, there has been an escalation in the concerns about trauma from repetitive physical activity. Thus, health-and-safety training specialists have shifted their atten¬tion to the recognition, evaluation and control of workplace hazards (Hancock and Hill, 1995). Recognizing that the spatial relationships of a workplace convey more information about hazards when experienced rather than described, trainers agree that simulation is the method of choice. Unfortunately, until recently, simulation systems were either simple software programs that did not come close to portraying the real experience or were complex hardware systems (such as flight simulators) that did, but at a cost of millions of dollars (Fritz, 1991). However, researchers and training specialists are excited about an emerging approach to work-force education based on virtual reality. VR is also described as cyberspace, immersive simulation, artificial reality, telepresence, virtual environment or virtual world (Meyer and Dunn-Roberts, 1992; Peterson, 1992). It represents a group of concurrent advances in computer and interface technologies. They enable an individual to interact in a multisensory way with a computer-generated environment. To achieve this, a typical VR system incorporates a computer that contains the necessary databases for producing realistic images and audio; a head-mounted display (HMD) or screen for viewing the images; and a three-dimensional controller, joystick or data glove for interacting with the computer-generated environment. If virtual reality is to become an effective tool for the safety training of mine workers, its attributes will have to be measured against other forms of delivery. Accordingly, Carr (1992) listed the following areas in which VR should be considered the method of choice: ? When training mistakes would be costly. ? When the necessary environment cannot be experienced in the real world. ? To build interfaces that are sensible and can be manipulated. ? To make training situations really "real." ?To make perceptible the imperceptible.

Jan 1, 1997

By Jay Parrish

Appalachian kimberlites appear to be spatially distributed along two structure parallel trends running from Tennessee to New York. It is hypothesized that the kimberlites were emplaced at the intersection of structure parallel basement faults and cross- structural lineaments. The latter are expressed in potential field and remotely sensed data. The western trend follows the Rome Trough from eastern Kentucky to south central New York. The eastern trend parallels the edge of the Ridge and Valley in Virginia and Maryland.

Jan 1, 1984

By Elif Çevik

This study deals with the mineralogical-geochemical characteristics and the industrial usage of the olivine from the dunites that crop out on the west of the Topuk village (Orhaneli). Mineralogical compositions of non-altered dunite samples are averagely as: Olivine (>90%), serpentine (1-4 %), opaque minerals especially chromite, magnetite, pyrite (1-3 %), and secondary minerals as magnesite, chlorite (1-2 %). X-Ray Diffractograms of the dunite samples indicate that olivines are in forsterite (93 on an average) composition, and chlinochrysotile and lizardite accompany to the forsterite. Chemical analyses of the dunites show that MgO, SiO2, Fe-,03 and LOI contents vary from 40,99 to 50,2 %, 34,67 to 40,6 %, 6,8 tol3,7 %, 0,11 to 11,27 %, respectively. SE-TAT Mining Company states that the study area has 400.000.000 tonnes proved, 800.000.000 tonnes probable and totally 1.200.000.000 tonnes olivine reserve. Consequently, all studies indicate that Orhaneli Olivin has convenient mineralogical and chemical properties and the grain size (0.04-40 mm) for industrial usages such as abrasive, olivine sand products, steel slag conditioner, balast and covering material in industry: Orhaneli olivines are demanded especially from the firms related to refractory industry, iron-steel factories, naval forces and shipyards. SE-TAT Mining Company also exports these olivines to different countries such as Macedonian and Spain.

Jan 1, 2005

By R. Fernando

"The Office of Mine Safety and Health Research (NIOSH-OMSHR) currently is leading an effort in the development of the next-generation self-escape apparatus as part of the research imperative directed by the MINER Act of 2006. A multifaceted contract program over the past 3 years delivered key components and base breathing modules to form the basis for developing backpack and vest-style versions of dockable self-contained (closed-circuit) self-escape respirators with hoods (CCMERs). This paper outlines the current status in developing the CCMER that incorporates a docking and switch-over valve (DSOV) for seamless transfer from one breathing device to another, and a hood with an inner mask and speech diaphragm (HMC) for ease of donning, ease of use, and communication ability. Three versions of the CCMER are being pursued, namely: the CCMER-B, which can be worn as a backpack and incorporates the features of a miner’s belt; the CCMER-V, which is worn similar to a miner’s vest and attaches to a miner’s belt; and the CCMER-C, a breathing module cached along the escape route that can be docked to the -B and -V versions. Human factors considerations are a key element in the CCMER design, as it is to be continually worn by the miner while underground, and must be readily accessible for deployment when needed. The CCMERs are designed to be capable of being certified to 42 CFR part 84 standards, including sub-part O for mine use, and to meet MSHA permissibility regulations for use in underground mines. They are sized for sufficient oxygen capacities (Cap 2 and Cap 3 as defined in sub-part O) to yield a duration that is of practical use in a mine escape scenario. INTRODUCTION The National Institute for Occupational Safety and Health (NIOSH) Office of Mine Safety and Health Research (OMSHR) is leading the development of self-escape apparatuses to provide breathing gas to mining personnel operating in the event of an emergency in various capacities underground in environments containing hazardous gas components. The Mine Improvement and New Emergency Response Act of 2006 (also known as the MINER Act) and input from the mining community called for the need to move Self-Contained Self-Rescuer (SCSR) technology to a next-generation status. In response to this need, NIOSH’s Office of Mine Safety and Health Research (OMSHR) established a strategic plan to develop key components and devices with help from external experts knowledgeable in breathing apparatus designs. The US Navy was identified as a key expert in this field through its extensive experience in diving apparatus and life support systems, and development work commenced through Inter-Agency Agreements with OMSHR. A contracts program was also launched with industry experts specializing in this field. This paper outlines the current status in developing the Next-Generation Closed-Circuit Mine Escape Respirators (CCMERs) that could be used for surviving and escaping from a mine following an emergency that renders the mine atmosphere irrespirable."

Jan 1, 2016

By Keith G. Wallace, Justus B. Deen, Daniel J. Brunner

This paper describes the impact of natural ventilation pressure (NVP) on the Nuclear Waste Isolation Pilot Plant in New Mexico (WIPP). The WIPP site is a U.S. Department of Energy underground facility for the disposal of low level radioactive transuranic defense generated waste. Because the facility is designed for the storage of nuclear waste, special design considerations are necessary to ensure containment of potential radioactive releases. The main design considerations which influence the ventilation system are the requirements of separate air splits for mining and storage operations and of air filtering before atmospheric discharge in the event of a radioactive release. The leakage between the two air splits must always be from the mining area to the storage area. The transient effects of natural ventilation pressures, caused by seasonal and diurnal surface temperature changes, impact the ventilation characteristics throughout the facility. This paper discusses the measurements taken to quantify the changes in NVP and the engineered systems designed to mitigate against the effects of NVP.

Jan 1, 1991