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By William C. Paschen

Damen Avenue to Roosevelt Road, the Tunnel and Reservoir Plan (TARP), a Deep Tunnel Project for the Metropolitan Sanitary District of Greater Chicago consists of 25,189 lin. ft. of 32 ft. tunnel with 1 ft. 0 in. concrete liner throughout. The 17,100 ft. main tunnel connects at both ends with two other Deep Tunnel contracts. A branch tunnel connecting to the mainstream tunnel, commences approximately 4,140 ft. from the construction shaft and runs 8,089 ft. south and terminates at the Racine Avenue Pumping Station. Shaft work consists of one 28 ft. 6 in. diameter construction shaft, one 3 ft. 6 in. diameter access shaft and 25 drop shafts-four of which have vent shafts. The drop shafts vary in diameter from 4 ft. 0 in. to 17 ft. 0 in. All shafts vary in depth to invert from 225 ft. to 235 ft. Work has been underway for 16 months and as of this writing the construction shaft and access shaft are complete. Seven shafts have been excavated and concreting operations have started in four of them. The starter tunnel is complete, the mining machine has mined 250 lin. ft. and the muck removal system is in full operation. The contractor for the project is a joint venture of Paschen/Morrison-Knudsen/Kenny. Paschen Contractors, Inc., Chicago, Illinois is the sponsor. The total contract amount is $107,837,300.00.

Jan 1, 1979

By Steven I. Majtenyi

INTRODUCTION The heavy risk inherent in all underground construction projects contributes significantly to the high cost of transportation tunnels. First, the knowledge of this risk leads the engineer to design conservatively. Second, the cost overruns are still common with a high proportion of them originating from corrective measures needed when unforeseen problems develop during excavation. These unforeseen problems includes - encountering unexpected objects, materials and water conditions - experiencing an unforeseen behavior of the materials - damaging property beyond the expected range of influence of the tunnel construction. To minimize these expenses, more emphasis is being placed on well planned and interpreted site investigation programs in the final design and planning stages of the project. It is well known that the cost of a planned excavation is less than the cost of dealing with the same conditions when they are encountered unexpectedly. Therefore, the objective of site investigation is to provide a complete set of reliable data for designers and contractors that is continuous along the projected tunnel alignment. Two alternatives axe available to achieve this objective; - for shallow tunnels, it is often feasible to generate continuous data by drilling appropriately spaced, vertical bore holes and applying sensing techniques for interpolation (1, 8). - for deep tunnels, or certain urban tunnels under existing structures, closely spaced, vertical bore holes are not feasible except for narrow zones at the portals. In such cases direct horizontal penetration may be required that may be complemented by radial sensing to extend the range of information.

Jan 1, 1976

By Dietrich F. C. Hudewentz, Alfred H. F. Lücker

For centuries tunnellers have made use of the experience of miners. In West German coalmining tunnellers have returned the impulses in recent years by giving the miners valuable stimuli with the result that a technology has evolved which benefits drill and blast heading, opens the door to TBM heading and has developed special measures for difficult strata conditions in deep coal mines. WHAT DO THESE ROCK HEADINGS LOOK LIKE? The main roadways dealt with in this paper have crosssections of 20 to 40 m2, big enough to allow the massive airflows needed to aircondition the mines. Because of the difficult strata conditions they have to be supported: in shotfired headings mainly with multi-element arches, in TBM headings with rings of 6 to 6.5 m diameter. In West German coalmining the majority of rock headings are blasted. The proportion of rock headings driven by TBM was 11 % in 1980 and 16 % in 1981, a rising trend expected to continue. Drill and blast headings Drill and blast headings are normally equipped with two or three-boom electro-hydraulic jumbos, electro-hydraulic crawler-mounted loaders with 1.2 m3 shovel capacity, a movable working platform and both chain and belt conveyors for dirt clearance to the minecar loading point. Fans and air-condition plant complete the equipment. Spacing between arches is usually 0.8 m. Investment for this type of mechanisation works out at around 1.3 m DM.

Jan 1, 1983

By John Hickey

Management teams at mining companies begin to ask themselves whether to take a company public and, if so, how to do it as they approach the normal threshold for going public in terms of revenue and operating performance. Today, the expense of going public generally suggests the company has at least $20 million in annual revenue and at least $2 million in cash. The revenue number can be lower for mining companies with large reserves. In order to properly attract the investing public, the company must also be operationally strong with robust prospects. The company should have a strong management team and a consistent history of double-digit growth that will continue into the foreseeable future. Assuming the thresholds are met, a company?s management needs to weigh the pros and cons of going public.

Jan 1, 2012

By John Dean

"Pumping backfilling medium used to fill in holes and caverns in mines is challenging. The often viscous, high solids materials are extremely abrasive and can destroy pumping systems in a matter of days. While a number of options are available, using a progressing cavity pump can often be the best solution. High pressure and capacity capabilities, coupled with low wear rates, ensures reliable cost effective operation.Thickened slurry backfilling for underground/excavation mining applicationsVoids and caverns develop as a result of mining operations penetrating deep into the earth seeking natural resources. After extracting all the ore from a mine, operators need to fill in these voids to preserve the integrity of the mine structure. They do this by pumping in a backfill medium. Each mine uses a different mix of components for backfilling, depending upon the mine’s specific structural requirements and environmental concerns, particularly water requirements. Most backfill mixes contain cement, or another cement-like substance, that acts as a binder to hold the backfill medium together. This is combined with tailings (unused rocks and waste from processing and/or extraction), and may also include chemicals or other binders to increase the material’s strength.Backfill pumping challengesPumping the backfilling medium can be a significant undertaking. This process involves transporting very viscous and high solid materials; the mix may contain 60-80 percent solids. These backfill slurries are extremely abrasive and the viscous material can wreak havoc with pumping systems. The material’s paste-like consistency presents problems for standard centrifugal pumps often used in other mining applications.Added complexity is posed when trying to achieve the required pressure, which depends upon how far away the material has to be pumped. It is not difficult to meet the pressure requirements if mixing the backfill material close to the area to be filled. However, pumping from extreme distances can be problematic — a great deal of pressure is required to transport the material from the mixing area to a distant backfilling site. Ideally, operators should be as close as possible to where they are filling, so they can use a smaller pump with lower power requirements."

Dec 1, 2018

By Dale A. Bivens

INTRODUCTION The Waste Isolation Pilot Plant (WIPP) is currently being constructed for the United States Department of Energy in SE New Mexico. The purpose of the project is to store low level transuranic waste in an underground environment which will ensure a safe atmosphere for the life of the stored waste. Ohbayashi was contracted by the DOE to sink two shafts and underground drift development which will be used to conduct a series of long term experiments in order to finalize the suitability of the geology and the environment for the transuranic waste storage. The two shafts sunk at the WIPP site were excavated around a borehole by conventional methods. The excavation around a borehole eliminates some of the established blind bottom sinking techniques, but creates unusual problems which must be pre-planned and scrutinized closely. An analysis of the slashing to the borehole technique will be given. WASTE SHAFT The waste shaft (w/s) is 5.8 meters (19 feet) in diameter and will be used primarily to transport the radioactive waste to the underground storage area. A pre-existing 1.83 meter (6 feet) diam borehole was taken to a depth of 655 meters (2150 feet) to the existing drift; at this level, a 38 meter (125 feet) sump was installed using blind bottom sinking techniques. Geology The primary geology for the w/s excavation is redbeds, anhydrites, dolomite, mudstone and

Jan 1, 1985

"The National Mining Hall of Fame and Museum (NMHFM) announced the 2017 National Mining Hall of Fame inductees. This year’s inductees, selected by the National Mining Hall of Fame’s Board of Governors, represent exploration and extraction of new frontiers, environmental stewardship, leadership in formulating U.S. mineral policy, education, and research and development, including the use of computers in planning, designing and managing mineral industry operations. The contributions of these individuals have undoubtedly had a significant and lasting impact on the mineral and mining industry. These individuals were selected for being visionary leaders, innovators, authors, pioneers in corporate social responsibility, and long-standing advocates for the U.S. mining industry.Dr. Thomas V. Falkie, Leonard Harris, Dr. Vincent E. McKelvey, and Gordon R. Parker will join 236 other mining industry luminaries when formally inducted into the National Mining Hall of Fame on Sept. 23, 2017. The 30th Annual Induction Banquet and Ceremony will be held at the Pinnacle Club, Grand Hyatt Hotel in Denver, CO.2017 National Mining Hall of Fame inductees:Dr. Thomas V. Falkie — In a career spanning six decades, Falkie’s accomplishments in industry, academia, government and professional societies demonstrate a pattern of integrity and sustained excellence. His gravitas and management style left highly favorable impressions in every position he held. He was the chairman and president of Berwind Natural Resources Corp.; President of SME; President of the American Institute of Mining, Metallurgy and Petroleum Engineers; Director of the U.S. Bureau of Mines and head of the Department of Mineral Engineering at the Pennsylvania State University. He played major leadership roles in the American Mining Congress, National Coal Association, Mining and Metallurgical Society of America, and the National Mining Association. He served on the board of directors of Foote Minerals and Cyprus-Amax and was very active in the National Academy of Engineering, the SME Foundation and the National Mining Hall of Fame and Museum.Leonard Harris — A highly regarded metallurgist and business executive, Leonard (Len) Harris may be most remembered for the heart he has for the people whose lives were touched by his career. For more than six decades, Harris has been a true pioneer in corporate social responsibility, leading companies to understand that doing the right thing for the local people is also the best path to business success. After an early career in Australia and Ghana, Harris moved to Peru in 1955 to join Cerro de Pasco Corp., owner of several mines with one of the most complex metallurgical operations in the world. Harris was quickly promoted through multiple positions and was ultimately named director of metallurgy."

Jan 8, 2017

By Bruce Watzman

Can the United States mining industry achieve its long-stated goal of zero fatalities ? and what will it take to do so? Does it require new laws and regulations, as some propose, and a continuation of the commandand- control model that has been born out of more than 40 years of regulation and enforcement under the Federal Mine Safety and Health Act of 1969? Or, is it time to consider a new model to manage safety and health and drive continuous, sustained improvement? These are questions that many are debating as mine safety performance, while improved, appears mired in a trough where improvement followed by declines seems to have become the rule rather than the exception. Without doubt, U.S. mines have made significant progress in safety performance during the last four decades, yet the stalled decline in fatality numbers, the industry?s report card of its success or failure, has led some to question whether the industry will achieve zero fatalities in U.S. mining by relying solely on the Mine Act?s framework and implementing its regulations. These are questions the CEO-led task force, set up by the National Mining Association (NMA), considered as it sought to identify impediments to zero fatalities posed by the current regulatory regime. Out of that effort came CORESafety, a common safety and health framework that relies on a management system approach to improve safety and health performance. The goal of CORESafety is to achieve zero fatalities and a 50-percent reduction in the rate of injuries in U.S. mining within five years ? 0:50:5. CORESafety is built on the plan-do-checkact model, which has been successfully deployed by industries, mining and nonmining alike, to drive continuous improvement in safety and health performance. The improvements in safety performance that can be achieved by shifting from a command-and-control regulatory approach to a risk-based systems approach built on the plando- check-act model have been documented in numerous industries. For example, the United Kingdom quarrying industry (Fig. 1), not satisfied with the number of reportable accidents being experienced 1995-2000, established a hard target of a 50-percent reduction in the number of reportable accidents during the period 2001- 2005. Having met this target, the industry then established a further target zero for the period 2006-2010. The mechanism to achieve these reductions? The plan-do-check-act model.

Jan 1, 2014

"The National Mining Hall of Fame and Museum (NMHFM) announced the class of 2019 National Mining Hall of Fame inductees. This year’s inductees, selected by the National Mining Hall of Fame’s Board of Governors, represent exceptional financial acumen in assembling several operations that formed the basis of a successful American mining company; conception and development of equipment which contributed to improved efficiency and mine safety; and unrelenting advocacy for the U.S. mining industry and its workers. These individuals, selected for being determined, forward-thinking innovators, doers and leaders have propelled the industry toward vastly improved safety and social responsibility.The Prazen Living Legend of Mining Award, named for renowned mining artist Gary Prazen, will also be presented at the ceremony. This award recognizes an individual or organization for significant and sustained commitment to educating the public about the relationship of mining to our everyday lives through educational materials, programming, and outreach.2019 National Mining Hall of Fame inducteesFrank Calandra, Jr. has devoted more than 50 years to the mining industry and he is an icon in ground control technology for the mining, tunneling and civil construction industries.From the ground up, his passion, sweat equity and shrewd business acumen have grown Frank Calandra, Inc. (FCI) and Jennmar from a single plant in Pennsylvania to a world-class enterprise with 25 plants employing thousands globally. As evidenced by Calandra’s more than 20 patents on ground control devices (not to mention the additional 80 patents his companies hold), his innovation and commitment to safety have made underground mining safer and more efficient. In the late 1970s and early 1980s, Calandra was instrumental in upgrading American Society for Testing and Materials (ASTM) standards in roof control for both state and federal regulations. Through his work with industry associations such as the National Mining Association, National Coal Council and Center for Energy and Economic Development, among others, Calandra has contributed his time, expertise and financial support to ensure a balanced political and regulatory climate for mining. Calandra is an inductee of the West Virginia Coal Hall of Fame."

Aug 1, 2019

By Larry Whittle

Gold milling activities generate waste streams containing dissolved metals and cyanide, among other contaminants, that require some form of treatment prior to discharging to the environment. To date, this treatment has involved the destruction of cyanide through natural degradation, chemical oxidation, or a combination of both followed by the precipitation of metal hydroxides. Although these processes have been proven to be capable of achieving. regulatory levels for metals and cyanide, they often generate significant levels of cyanate and, at times, ammonia, that may be toxic to rainbow trout and thus undesirable for regulatory compliance. Tallon Metal Technologies Inc. (Tallon) has developed Vitrokele™, a chelating resin that has the ability to capture metals (including gold), both total and weak acid dissociable cyanide, as well as thiocyanate from both slurries and solutions. The loaded resin is eluted and returned to the recovery circuit while metals and cyanide are recovered from the eluent stream. This process was demonstrated at pilot scale at B.P. Resources' Hope Brook Gold Mine in Newfoundland, and more recently at Canamax's Bell Creek Mine near Timmins, Ontario. The results from these pilot programs showed metal and cyanide recoveries of 99% or more with the concentration of cyanide and metals in the effluent reduced to levels with minimal or no toxicity to rainbow trout. Furthermore, neither cyanate nor ammonia were generated from the process. The loaded resin was effectively stripped and re-introduced to the recovery circuit; cyanide was captured in the eluent stream and made available for recycling to the mill leaching circuit; and metals were captured for re-use, sale or disposal. This paper summarizes the results obtained from the pilot tests at the Bell Creek and Hope Brook Gold mine sites.

Jan 1, 1992

By Scott W. Beckman, Leslie C. Thompson, Joseph A. Kizis

Heap leaching of ore with cyanide is a common and economical means of extracting precious metals (gold and silver) from mined ore. The use of cyanide, and the heap leach process, can seriously impact the environment. In the worst case, catastrophic failure of containment structures can release toxic levels of cyanide into receiving bodies of water, resulting in toxicity to ecological communities and contamination of public water supplies. Furthermore, cyanide degradation products such as nitrates can also impact local streams, lakes, and aquifers. Even if cyanide can be removed, the crushed residual ore may generate acid solutions that can release toxic heavy metals into the environment. Pintail Systems, Inc. (Pintail) of Aurora, CO, in conjunction with technology partners Science Applications International Corporation (SAIC) and Fairmile Gold Corporation (Fairmile), have developed a microbially-based precious metal lixiviant that can be used as an alternative to cyanide. The microbial process, called BioLix, is Pintail's second-generation biotechnology product for the recovery of precious metals from ore. The BioLix process is based on the enzymatic induction of organic lixiviant compounds using proprietary inducing agents and microorganisms. The process operates at near neutral pH and ambient temperatures using non-pathogenic microorganisms and food-grade chemicals. Precious metal extraction is also enhanced through the employment of microorganisms that facilitate mineral-solution reactions such as surfactant generation (improved wettability), and oxidation of gangue minerals that expose mineral surfaces to leaching. In order to demonstrate the effectiveness of the BioLix process, results from laboratory bench-scale experiments and a column study are presented. In addition, new applications for this enabling technology are discussed and include re-leaching of spent ore heaps, in situ leaching, and cyanide replacement for heap leaching.

Jan 1, 2000

By Chee Theng

"Mining professionals are a resilient lot. Sure, copper prices are dismal, permitting processes seem interminable and the top mining companies are shedding jobs like a Shetland sheepdog sheds hair. All the more reason to hone technical skills, reconnect with old contacts and get one’s finger on the pulse of the industry.More than 400 did just that in the balmy sunshine and among the saguaro cactus of the Tucson venue of the SME Arizona Conference.Giving the keynote speech was Patrick Merrin, vice president at Hudbay Minerals (see box), while the luncheon speaker was University Distinguished Professor Mary Poulton, director of the Lowell Institute for Mineral Resources at The University of Arizona.“Attendance was great, especially given the copper price,” said Ta Li, vice president of business development at Tetra Tech and 2001 SME President. “The luncheon speaker was one of the better ones in recent years. Her talk contained a lot of fresh ideas, and practical versus theoretical concepts.”Talk about values, not economicsPraise was unanimous for Poulton, who gave a thought-provoking talk on “The New Face of Mining: The Culture Change for Compatible Mining.” Corporate social responsibility has been embraced by the metals mining industry, and it’s being done right, she said. “So why do we have more conflict? Why are there more protests? Why does permitting take longer and longer?” Poulton made a case for an approach based on compatible, rather than sustainable, mining to present a new face of mining that can be compatible with communities, cultures and the environment, and still be profitable. When the mining industry starts to talk about compatibility between what it is doing and what “me,” as the consumer, wants, what “we,” as citizens of a community, want, and what’s good for the “world,” we’re going to see the next culture change happen, she concluded."

Jan 1, 2015

Automated drilling in surface mines is here, it?s successful, and it?s already at work in mines around the globe. Coal, copper, iron and gold mines in large mining countries such as Canada, Australia, South Africa, the United States and Chile are meeting mining objectives previously ruled out as unattainable. Pit Viper automation enables operators to accomplish more objectives safely. Operator assist functions like AutoLevel, AutoDrill, Auto Rod Changer and multi-rig teleremote control are a few of the features mines are using to gain consistent, sustainable productivity.

By William Gleason

"Technology of all forms has experienced exponential growth in recent years, and there is no sign of it slowing down. This growth has presented amazing opportunity and significant challenges in nearly every aspect of daily life. Some of these changes are seen and experienced every day as we turn to our smart phones, tablets and smart watches to help with us with everything from directions to the store to managing our health. And other technological growth takes place far away from the public view but can have as much of an impact on our daily life as does shopping at Amazon or connecting with friends on social media.At the “THRIVE 2018, Innovations Advancing Mining” conference presented by SME on Sept. 27 at the Sheraton Pittsburgh Hotel at Station Square in Pittsburgh, PA, the focus was on innovation and how it affects the global mining industry.More than 100 people were on hand for the inaugural event, and they were treated to a unique program that focused on the cutting-edge innovations that will carry the mining industry into the future while increasing safety and productivity along the way.2018 SME President Barbara Arnold was the driving force behind the conference and put together the technical program with a focus on innovation through the entire mining life cycle and into the future. Talks ranged from more efficient and safer ways to extract minerals to some of the most advanced end uses of minerals and metals, including the use of 3D printing to create precision parts for machines and humans from advanced metal alloys.“We need to adapt new technologies to our industry and develop additional technologies as we provide materials and metals for infrastructure and energy development in the United States, around the globe, and to the Moon and beyond,” Arnold told Mining Engineering. “Our inaugural THRIVE conference sets the stage for these innovations to be applied and to continue to be developed. Our mining industry can only continue to thrive with these advances.”"

Jan 11, 2018

By R. H. Busch, S. M. Loscutoff, F. T. Cross, R. E. Filipy, P. J. Mihalko, R. F. Palmer

INTRODUCTION During the last decade, several studies in France (e.g., Perraud et al. , 1970; Chameaud et al., 1974, 1979 and 1980) and the United States (e.g., Stuart et al., 1978; Cross et al., 1978, 1980 and 1981) have demonstrated the systematic production of emphysema, fibrosis and tumors in the lungs of animals exposed to radon daughters alone or to mixtures of uranium-mine air contaminants. The studies in beagle dogs have been particularly interesting because of the uncertain etiology of the disease and the (apparently) diverse results of the studies at the University of Rochester and the Pacific Northwest Laboratory (PNL). In the Rochester studies, reported by Morken (1973), beagle dogs were exposed to "normal" room air dust loads and radon daughters from 200 to 10,000 WLM*, delivered in 1 to 50 days (rate of delivery, about 200 WLM per day of exposure). Histological examination of tissues was conducted at 1, 2 and 3 years after exposure for all exposure levels. No cancers were noted in these dogs that received estimated alveolar doses of 34 to 1700 rad (0.34 to 17 Gy). Pathologic changes were found only in the alveolar and bronchiolar regions of the lung. These changes were small, subtle, variable, and widely separated, involving only a very small fraction of lung tissue. Lesions appeared as focal thickening of alveolar septa, with some metaplasia of alveolar cells and some hyperplasia of bronchial epithelium. In the PNL experiments reported by Cross et al. (1978), beagle dogs were exposed in lifespan studies to mixtures of radon daughters (rate of delivery, about 14 WLM per day of exposure), uranium ore dust and cigarette smoke. One group of dogs was exposed to cigarette smoke alone. Except in control and smoke-only groups, the dogs died within 4' years of the first radon daughter exposure, or were killed when death appeared imminent because of pulmonary insufficiency (characterized by rapid, shallow breathing). Control and smoke-only animals were killed at periods corresponding to highmortality periods in the groups exposed to radon daughters and mixtures of uranium ore dust and cigarette smoke. Emphysema and fibrosis were much more prevalent and severe in the lungs of dogs exposed to the mixtures. These dogs also had adenomatous lesions, which progressed to squamous metaplasia of alveolar epithelium, epidermoid carcinoma and bronchioloalveolar carcinoma. Pathologic changes in the upper airways of these dogs were most prominent in the nasal mucosa, and included a few squamous carcinomas in the nasal cavity. Respiratory tract neoplasia was noted after ~4 years exposure and at cumulative exposures exceeding approximately 12,000 WLM. Apart from differences in associated carrier aerosol (room air dust vs. uranium ore dust) and radon-daughter exposure rate (200 WLM/day, shortduration exposure vs. 14 WLM/day, long-duration exposure), the most obvious difference in the Rochester and PNL studies was the observation time following exposure (3 years maximum vs. >4 years). Although neoplasia may not have been observed in the Rochester animals because of the earlier termination of the experiments, it is surprising that other lesions, such as prominent fibrosis and emphysema, were not reported. A follow-up study (reported here) is currently in progress at PNL to determine the pathogenic role of uranium ore dust alone and, in particular, to clarify the role of the ore dust in the production of the massive pulmonary fibrosis observed in the earlier study. Pulmonary function testing (a recently acquired capability) was included in the follow-up study as an indicator of progressive change in lung tissue. MATERIALS AND METHODS Chronic (4 hr/day, 5 days/week) exposures began when the dogs were about 2 1/2 years old. Two identical exposure chambers provided space for simultaneous, head-only exposure of 24 dogs to ~l5 mg/m3 carnotite uranium ore dust. An aerosol diffusion system was incorporated in each chamber in order to channel fresh aerosol past each dog's head; uranium ore dust was added to the inlet room air with Wright Dust Feed Mechanisms* (WDFM). Uranium ore dust and condensation nuclei concentrations were measured daily; chamber aerosols were monitored occasionally for particle-size distributions as described for previous hamster experiments (Cross et al., 1981). The carnotite ore used in these experiments, from the Mitten mine in Utah, was furnished in 1970 through the Grand Junction, CO Office of the (then) U.S. Atomic Energy Commission (now the Department

Jan 1, 1981

By Mike Ghassemi

It is clear that precise overground and under-ground mapping is an important factor for all designers. Due to rapid changes in underground construction, tunnel designers are increasingly in need of updating project information. This article explains the latest techniques for detecting under-ground utilities as well as underground mapping. Global Positioning System (GPS) is a very ac-curate and popular navigation and mapping system that has been used extensively above ground, but is not used for underground mapping as signals are not strong enough to pass through ground or water. Most underground techniques were developed for military applications during the first and second world wars. Later, the techniques became public. For example, ground penetrating radar was developed for the military in 1970 to be used for locating tunnels under the demilitarized zone between North and South Korea. Later, the same technique was used for detecting unexploded ordinance such as plastic land mines.

Jan 1, 2011

By S. D. Rosenthal

"This article will share my ‘shift in career direction’ journey from corporate mine engineer, with 31 years of mining various commodities with a wide range of responsibilities in a variety of countries, to the world of academia. There are times in one’s career that a change is required, albeit perhaps not as drastic of a change as moving to teaching. This paper will share how the transition arose, the decision to make the change, the challenges of the first year in academia and the journey within academia going into the second year.As a graduate of the Montana College of Mineral Science and Technology (Montana Tech) with a B.S. mining engineering degree in May of 1982, my first job with Utah International in the Farmington, NM area took me back to my home state of New Mexico. Some of you will remember that the early 1980s was not a period of prolific opportunities for mining engineers, given low commodity prices, especially for copper (for example, Anaconda Co. had been taken over by Arco and was in the midst of closing down its Butte operations). Coal was good and the learning opportunities abounded with Utah (which became BHP and then BHP Billiton).Gold was taking off in the mid to late 1980s thanks to use of cyanide and heap leaching technology improvements, coupled with deregulation of the gold price, so I ventured off to work in the gold industry with a (then) junior Canadian company called Barrick at a new acquisition of theirs known as Goldstrike. That same gold surge was causing a shortage of iron ore mining engineers in Australia. So after a few years in Nevada, I uprooted the family and left for a little town in the Pilbara of West Australia, known as Newman, to work in the iron ore industry with BHP Iron Ore. An initial short overseas posting turned into six plus years before transferring to BHP’s Indonesian steam coal mines in Kalimantan on the island of Borneo. BHP was going through a rough period following some ill-fated projects (Magma Copper purchase, Beanup and HBI) and was reviewing assets and staffing, so internal opportunities became scarce. Employees were encouraged to “leave the company and find work elsewhere.” So, off I went to Argentina to try copper mining in the Andes with Minera Alumbrera. This short stint in South America was followed by a move to another mining town, Morenci, AZ, and a posting with Phelps Dodge (now Freeport- McMoRan). After 12-plus years without living close to snow, we moved to the Denver, CO area in a new position with Newmont Mining Corp. Along the way I became a professional engineer (Nevada) and completed a masters in project engineering and management. After 11 years with Newmont, I moved to Butte, MT where I accepted a position as assistant professor of mining engineering."

Jan 1, 2015

Several major impediments threaten the successful delivery of tunnel and under-ground construction projects. In addition to technical design and construction risks associated with tunnel projects, many of which are well understood, budgetary pressures, funding constraints and the complexity of procuring, administering and executing multiple concur-rent projects in a large program could also have a catastrophic impact on the program?s objectives. Contributing factors often include poorly managed design, procurement, construction, managerial, organizational, market and stake-holder risks, as well as nonconforming inputs or outputs to the costs and schedule, or any other potential inabilities to deliver the required or desired results. A strategy to prevent ?failure? of a project requires a proactive and holistic approach to risk management. Through planning, identification, analysis, management, monitoring and control of the project?s risks (both threats and opportunities), attention to management of risk will in-crease the probability and impact of positive events and decrease the probability and impact of events adverse to a project?s objectives.

By A. Frank Alsobrook

DOUG HALBE: Thanks, Terry. And in spite of your introductory comments, I'm going to attempt to continue our hallowed tradition of saying nice things about the speakers. This is really a serious comment now. We, as mineral processing and mill people, don't often talk to people outside our general operating area. One thing that we've tried to do in this operators' symposium is get speakers from various types of plant operations to help illustrate all the things we have in common. Our next speaker is from the industrial minerals area. I think there's a lot to be learned from industrial minerals operations. Some of the people in the last session learned some things about fine grinding in industrial mineral operations. I was a little surprised to see people there grind to 2 microns. Our next speaker is Frank Alsobrook. Frank is another nonmetallurgical engineer. He has a degree in geology, a master's of science from the University of Wisconsin. He's had his own very successful consulting company for a number of years. This is your 11th anniversary, Frank? Very good. He's also the immediate past chair of the industrial minerals division. I think the folks at the speakers' table should be ashamed. You have been so rowdy that Frank chose to sit in the audience. [laughter] We'd like you to come up now, Frank, and tell us some things that you've seen that might be useful to us. INTRODUCTION FRANK ALSOBROOK: The three topics addressed briefly are (1) teamwork and operations modeling, (2) the pitfalls of capital conservatism, and (3) the potential for by-product recovery. Ideas for improvements in these areas are not unique to industrial minerals but apply to metal mining and processing operations, as well. Several additional topics are suggested at the end of the paper.

Jan 1, 1998

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's modulus, (6) Poisson'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