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By A. M. Gaudin

This year the American Institute of Mining, Metallurgical and Petroleum Engineers has chosen to give me its Robert H. Richards Award, a distinction which is widely regarded as the highest honor in the field of mineral engineering. I am deeply moved by this tribute, which suggests not only regard for my service to the profession but also the affectionate esteem of my fellow mineral engineers. You have made me happy at the prospect of the permanent association of my name with that of Robert Hallowell Richards and of the distinguished recipients of the award, Arthur Fay Taggart, Frank R. Milliken, John F. Myers, Edward William Englemann, C. Harry Benedict, Edward W. Davis and Arthur W. Fahrenwald. I wish to thank you all for an honor so generously bestowed. Professor Richards is known to us all as a legendary figure, and we can read about him in the Richards Memorial Volume of our Transactions. Some of us have even had the good fortune of knowing him. I count myself among those lucky few. In its intangible attributes the Award recalls those things for which Professor Richards stood: for Science in Art, for thoroughness, for meticulous accuracy, for bold imaginativeness, most of all for professional integrity. Now, as in his day, these attributes are central to an engineer's creed. They are appropriately needed in a formulation of a definition of the mineral engineering profession.

Jan 6, 1957

By G. Brackebusch, S. J. Jung

Backfilling techniques are widely used in large-scale underground mines. Massive pillars, which have been left in place for stability, limit mining activity. Backfilling allows safe recovery of the ore remaining in pillars and assures long term stability. In deep mines expected high stress can be relieved with the backfill. Initially, waste rock was used to fill the openings with mixed results. The need to improve safety and reduce costs has prompted the industry to investigate alternatives. Hydraulic filling with Portland cement added has shown considerable promise, but little has been done to define the parameters of design effective system. The purpose of this study is to determine the relationship between backfill and mining components that can be used to effectively design a best-case hydraulic backfill.

Jan 1, 2000

By E. A. Metz

Perfect combustion in an engine would produce only water vapor, carbon dioxide and nitrogen as by-products; however, complete combustion is never achieved. As a mobile power plant, the diesel engine is relatively inefficient in terms of energy produced from the energy potential of the fuel. The diesel is not a perfect engine. The fuel burned can undergo a very large number of reactions in the combustion chamber. It only stands to reason that a large number of compounds are contained in the exhaust, actually, thousands of chemicals. The exhaust can be broadly divided into a gaseous phase and a particulate phase. Each phase is made up of organic and inorganic compounds. The vapor phase contains carbon monoxide, sulfur dioxide, various oxides of nitrogen and many hydrocarbons. The particulate phase contains clusters of respirable inorganic particles made mostly of carbon. This paper will address the health hazards, as we know them today, of the major components of the particulate phase in the exhaust of diesel engines. It will briefly examine the operational factors of the diesel engine as it applies to particulate emissions. Longitudinal studies of occupationally exposed miners are needed with documentation of levels of exposure before a chronic effect of exposure can be determined. At this time, it is not possible to conclude from human studies the level of diesel exhaust exposure that results in the observed lung cancer risk.

Jan 1, 2001

By AIME AIME

THE 131st meeting of the American Institute of Mining and Metallurgical Engineers was held in New York on Feb. 16 to 20, 1925, with the largest registration of any previous meeting, the total being 1320 compared to 1276 in 1924. The technical sessions were more largely attended and aroused more discussion than ever before. There were joint meetings with the Mining Section of the National Safety Council, under the auspices of the Industrial Relations Committee of the Institute and two very important lectures, the Howe Memorial Lecture, under the auspices of the Iron and Steel Committee, and the lecture by Dr. Carl Benedicks, of Sweden, on Corrosion, under the auspices of the Institute of Metals Division. The Petroleum Division conducted its annual Symposium on Oil which will be published later in book form. At the annual business meeting on Feb. 17, the following ticket was elected, and the reports of the President, Treasurer, and Secretary 'were presented:

Jan 1, 1925

By T. A. Marcotte, D. J. Bobrow, S. Vaghar

This paper discusses the geotechnical instrumentation program on the Central Artery/Tunnel Project, in Boston, Massachusetts. Particular attention is given to a state of the art Graphic Information System (GIS) application which has been developed for rapid analyses and reporting of data. This application will see extensive use during the ongoing complex downtown tunnel construction. The excavations in soft ground require cuts of up to 120 feet deep and 250 feet wide. Deformation and groundwater monitoring instruments have been installed to monitor the stability of the excavation support systems and the abutting buildings. The use of this application is illustrated with an example from an ongoing contract.

Jan 1, 1997

By G. R. Mansfield

THE geologic structure of the Idaho phosphate field has an important bearing on the classifica-tion and the exploitation of the lands that contain phosphate. Maps and structure sections1 recently made available show that the phosphate is mainly preserved in downfolded or downfaulted areas. Since the phos- phate beds are generally rather soft and lie between harder and thicker formations they have been forced to adjust themselves to these formations during epochs of disturbance of the earth's crust, so that they are frequently affected by minor folds and by faults which may help exploitation by producing undue thickness at certain places or may hinder it by cutting out the phosphate at other places where according to expecta-tion it should be present. A particularly important structural feature which affects both the distribution and the exploitation of the phosphate beds is the great Bannock overthrust by which one or more slices or blocks of the earth's crust have been pushed over other blocks like ice cakes on a pond. Thus in this region a great flap of folded rocks lies across other rock structures for a distance of approximately 35 miles. Most of the commercially accessible phosphate deposits, shown in the maps that accompany the report cited, are in this flap, which con-stitutes the upper block of the overthrust. In some places, however, the phosphate in the lower block is also accessible. In both blocks post-phosphate rocks exposed at the surface here and there indicate that phos-phate beds may lie at greater or less depth below. The presence of the Bannock overthrust beneath much of the area reported is known by the occurrence of windows in the upper block both within the quadrangles mapped and in areas farther west. The portions of the lower block exposed in these windows show stratigraphic dis-cordance with the surrounding formations. The depth of the fault plane at most places, however, can be told only by drilling or actual mining. Some of the folds in the upper block are relatively deep and it seems fairly certain that the phosphate that may originally have been present in their deeper parts has been removed by thrust faulting. The estimates of phosphate reserves in folds liable to be affected by the Bannock overthrust may therefore need ultimate revision depending on the depth of this fault plane, as it may subsequently be ascertained.

Jan 1, 1928

By W H. Poole, E. R. W. Neale

A new style of tectonic map based on age of folding has been prepared for the Canadian Appalachian region as part of the Tectonic Map of Canada Project. This style of map pro-vides a clearer picture of the tectonic history of the region than any meth-od hitherto attempted. Precambrian blocks that were relatively unaffected by Palaeozoic de-formation are distinguished on the Great Northern Peninsula and in the Conception Bay region of Newfound-land. K/ A age determinations suggest that these blocks were intruded and metamorphosed during Grenville orogeny. Other Grenville-like rocks, on Cape Breton Island and in New Brunswick, were more actively involved in subsequent Palaeozoic orogeny. Taconic orogeny, the first phase of Palaeozoic deformation, took place in Middle and/or Late Ordovician time and was accompanied by intrusion of ultrabasic rocks. Evidence of the -

Jan 1, 1961

By Karl A. Higgins

In August 2004, the long-awaited National Harbor project in the DC metro area sprang to life with the design of Gaylord National Resort and Convention Center. When the project was in its final stages of construction in 2007, it was noted as largest building development of the east Coast and the 4th largest Building project in the U.S. The final construction costs were above $900M and it served as the catalyst for the overall National Harbor development which added another $1B in construction costs over the next few years. The Gaylord Hotel is supported by approximately 150,000 linear-feet of driven precast concrete piling, one of a handful of major DC area projects in the early 2000s that were supported by this pile type. The project overall was a success, but the fast-paced construction schedule created significant challenges to the designers and contractors. Piling installation was the first major building construction task, and it did not start out well. While the test piles were installed without damage, when production pile driving began in the summer of 2005, pile head and body breakage soon became evident. Typical of most highprofile projects, there are many stakeholders involved and an equal number of opinions on why the piles were breaking. The financial and contractual implications of starting the project off awkwardly were evident to all. The pile driving criteria was scrutinized by the contractor, and the engineer’s had reservations about the size and type of the hammers used for pile driving. Ultimately, it was proven the leading cause of pile breakage was neither the pile driving criteria nor equipment, rather the pile materials themselves. The author of this paper is also the Geotechnical Engineer of Record for Gaylord National and many of the adjacent National Harbor buildings including the recently completed MGM casino. About 100 piles were damaged during Gaylord’s construction some requiring multiple piles for replacements. Over the past decade or so, rumors on the causes of the pile breakage have spread in the market, with some alleging this pile type is not compatible with the geologic setting. I have purposely avoided writing this case-study due to the controversy surrounding the subject, but now some 15 years later it seems appropriate to do so considering DFI’s annual conference location. This will be a fact-based assessment of pile breakage at Gaylord and will also include a comparison to the neighboring buildings where far fewer driven piles were damaged, once a more appropriate concrete mix design was required. The pre-cast supplier is no longer in business.

By William Gleason

"In 2008, the world quietly hit a milestone that did not receive much fanfare or publicity, but it hit one that marked a turning point in the history of mankind and the way the planet is and will be inhabited in the future. It was in 2008 that, for the first time, more than half of the world’s population, an estimated 3.3 billion people, resided in urban areas. The world’s population had moved from being a majority of agricultural and rural society to an urban society. Andrew Whalley, deputy chairman for Grimshaw Architects, said this change in where and how people live will continue to increase urban populations and, by 2050, it is estimated that more than 6.4 billion people will live in urban areas. To meet these needs, Whalley, speaking during the keynote session of the 2105 Cutting Edge conference in Denver, CO, said future cities will have to be reimagined and redesigned to be more efficient. A large part of that design will be in the infrastructure of those cities.At the Fourth Annual Cutting Edge Conference, Sept. 21-23, much of the discussion was around how the tunneling and underground construction industries improve cities in a number of ways, including societal, environmental and in overall efficiency. There was talk, not just about the improvements that society enjoys at the completion of such projects, but also about the challenges faced by the owner and contractor in the construction of such projects.The conference, titled Urban Tunneling, brought together some of the top minds in the industry to not only discuss the issues faced today, but also those that will shape the industry in the future.For his part, Whalley spoke about a number of projects around the world and how they have impacted society in ways beyond simply providing a better means for transportation of people or water. Notably, he spoke about the Crossrails project in London.London is a city of 8.6 million people and a history that dates back nearly 2,000 years. It is a great example of the challenges the industry faces in bringing modern efficiencies to an established city.Running more than 100 km (62 miles) with more than 42 km (26 miles) of tunnels passing through 40 stations, including 10 new stations, the project is the largest in Europe and will transform the way people move about the city."

Jan 1, 2015

By J Harris, M Shi, S Vink, P A. Kirsch

Across the life-of-mine, water is both an essential commodity to mining, and one of the most significant hazards. In Australia, a land of drought and floods, availability of water is a critical strategic risk for mine sites and neighbouring stakeholders, with both insufficient water leading to curtailed operations and contested space, and extreme water closing operations through flooding of mine sites, transportation infrastructure and unplanned regulatory restrictions. In addition to these major strategic risks, water must be addressed in operational risk management activities in many different ways.This paper develops a set of categories for classification of water risks based on academic papers from the water in mining literature. These categories are applied to media content analysis of articles in International Longwall News (ILN) (an online coal industry news site) obtained with the search terms ‘water’, ‘rain’ and ‘flood’. Identified risks are discussed within the context of the life-of-mine. The paper uses these same categories to analyse the treatment of water risks in a new coal industry risk management body of knowledge called RISKGATE (http://www.riskgate.org, Minerals Industry Safety and Health Centre, The University of Queensland). The discussion of water risks in both INL and RISKGATE is compared and contrasted to pinpoint opportunities (and a roadmap) for further development of a specific RISKGATE water module for site-based operations. The media review also identifies areas for development of RISKGATE expansion topic(s) that would address other strategic water risks, eg severe weather events.CITATION:Shi, M, Kirsch, P A, Vink, S and Harris, J, ?2014. Water as risk in mining – media analysis and the RISKGATE body of knowledge, in Proceedings Life-of-Mine 2014 , pp 205–218 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By S. K. Kawatra

It is common in coal-cleaning operations to produce a fine waste stream which contains a considerable amount of coal, but which is not economical to recover both because it is mixed with large amounts of difficult-to-remove clay slimes, and because the fines are often heavily oxidized. Conventional froth flotation machines cannot produce an acceptable product from such material in a single stage of flotation, and even flotation columns often have difficulty cleaning this type of feed. A new type of flotation column was designed specifically to deal with these problems, and was installed and tested in a coal-cleaning plant in Ohio. The feed coal contained 39.8% ash as fine clay, and 2.83% total sulfur, and was 80% passing 176 micrometers. The coal was a thickener product which had oxidized for some time, and was very difficult to float. However, using the new column it was possible to recover up to 85% of the calorific value in a product containing less than 11% ash, and up to 60% of the calorific value in a product of less that 8% ash. The bulk of the pyritic sulfur was rejected from the coal as well. Multistage flotation tests showed that the flotation column was able, in a single stage, to produce the best froth flotation product that it was possible to recover from this coal.

Jan 1, 1994

Acid soluble calcium is depleted in drainage sediments from hydrothermal alteration centres in the Coromandel Peninsula. The routine analysis of acid-soluble calcium on drainage samples is an economical and effective technique for outlining hydrothermal alteration centres in volcanic terrains.

Jan 1, 1979

One of the critical challenges facing the mining industry ? and not just in the United States ? is the looming labor shortage. A significant percentage of the industry?s professional workforce is, well, getting old, and many will be retiring in the next 10 years or so. This is not a new issue to the industry. It has been discussed at various industry meetings and conferences for many years. How does mining, with its largely negative public image, attract young people to mining schools? And, equally important, who is going to teach them? Mining schools, what?s left of them in the United States, are beginning to lose qualified faculty to retirements, and no one is available to replace them. SME addressed this issue during the keynote session at its annual meeting in February in Denver, CO. This year?s theme was ?Mining: It?s About the People.? Despite a blizzard that blanketed the city on the day most attendees were to have arrived, the meeting still attracted a record 7,202 people. And the accompanying exhibit sold 822 booths, also a record. The U.S. Department of Energy?s National Energy Technology Laboratory contracted with the National Academies? National Research Council to complete a study concerning the availability of skilled workers to meet the energy and mineral security requirements for the United States. The National Research Council, in turn, asked SME to collect and analyze workforce trends in these industries. The result of SME?s analysis is the report ?Emerging Workforce Trends in the U.S. Energy and Minerals Industries.? It is available on the SME website, www.smenet.org. Click on Government Affairs. While the report did not paint a completely dismal picture, there were some disturbing results. It concluded that within 20 years there will not be a sufficient number of skilled professionals to satisfy the labor demand. That said, the report said that most of those positions would likely be filled. However, the U.S. mining will go through a period of time when the workforce will be made up of very young and senior workers.

Jun 1, 2013

By D. Harrington

"Coal—mine explosions are accidents that can and should be prevented. In former years hundreds of lives were lost each year in the United States as a result of such explosions, but after 1932 the numerous precautionary measures adopted had reduced their frequency and severity 75 percent or more until in 1940 several very disastrous explosions marred the good record. Unfortunately, both the number and severity of explosions seem to be tending to increase compared with the relatively good achievement from 1933 to 1940. The requisites for an explosion are ever present in all soft-coal and many hard-coal mines. A certain combination of circumstances, such as a flame or an arc in a cloud of dust or in a body of gas or both may start an explosion at any time. The fact that the frequency and severity of explosions were lowered for 6 or 7 years is no guarantee that such freedom from explosions will continue, as the bad record of 1940 has shown, and underground workers should feel honor bound to exercise the utmost care so that they will not help to bring about the circumstances that will cause an explosion.Although mine operators bear the main responsibility for preventing explosions, miners can do many things to help. As about 9 out of 10 explosions begin at a working face, it is largely within the power of workers to prevent them. All miners should do their part willingly and should not defend a fellow workman from punishment, even from discharge, for disobeying necessary rules, whose disregard may cause the death not only of the safety-rule breaker but also of many of his coworkers.When a miner is careless and is injured some other way than by an explosion he may be the only one to suffer, but if his carelessness causes an explosion he not only endangers his own life but also that of every other man in the mine and possibly the lives of persons outside the mine.Experiments have shown that ignition of as small a quantity as 150 cubic feet of an explosive mixture of methane and air under certain circumstances can start an explosion that will traverse an entire mine. Thus, ignition of an explosive mixture of gas 1 foot down from the roof and 13 feet back from the face of a 12-foot entry might cause a widespread explosion if the right quantity and kind of dust were present. Many persons have ignited much larger quantities of gas without being killed, but they survived only because dust, confinement, and other conditions were not exactly ""right."""

Nov 1, 1940

By JSrvinen A, Yll÷ E

At Cominco's Zinc Refinery at Trail, British Columbia impurities are removed from zinc sulphate electrolyte by a two-stage purification process using zinc dust. Copper, cadmium and thallium are removed in the first stage whereas cobalt is removed in the second stage. Cobalt removal kinetics are affected by soluble antimony and copper additions to the electrolyte. This study was focused on the kinetics of cobalt removal by zinc powder cementation. Experimental variables included copper and antimony concentrations, pH and temperature. Common organic additives employed in zinc plants were studied to determine potential interactions with the cobalt removal process. Cementation products obtained from laboratory experiments and plant practice were studied using SEM. A number of significant results were obtained: 1. Copper and antimony ions were sustantially removed from solution during the early stages of the cementation reaction (within the first 15 minutes). Cobalt cementation kinetics are slow and follow a first order kinetic regime. 2. A drop in the cobalt removal rates can be correlated with a rise in the Eh of the slurry. 3. Ligninsulphonate, Percol 351 and animal glue at levels of 2 mg/L significantly impede cobalt cementation.

Jan 1, 1993

Bitumninous and semianthracite coal reserves underlie about 1,400 square miles of Arkansas, less than 2.7 percent of the state's total area. These deposits, located near the western border, contain an estimated 2.2 billion tons, of which about half are recoverable. This represents less than one-tenth of one percent of the national reserves. Most of the commercial coal is mined from thin beds that are at least 14 inches thick. In some locations, however, the coal beds can be as much as eight feet thick. Lignite was mined in southern Arkansas before the Civil War. Current estimates indicate that the reserves may be as high as 9 billion tons, which could be used in the state's coal-fired electric generating plants; however, these deposits are not being mined at present. Because many coal operations in Arkansas are small and the demand for coal is unsteady, the industry employs fewer than 25 miners on a daily basis. Arkansas gained primacy when its regulatory program was conditionally approved November 21,1980, subject to the correction of four minor program deficiencies. The regulatory program was fully approved January 22, 1982. Authority of the state to administer its Abandoned Mine Land Reclamation Program was granted upon approval of the Arkansas Reclamation Plan on May 2, 1983. Arkansas was the first state to assume responsibility for abandoned mine land emergency projects when its Reclamation Plan was approved.

Jan 1, 1992

By Anahita Modiriasari, Benjamin S. Rivers

Measurement while drilling (MWD) is a subsurface exploration technique associated with real-time and continuous monitoring and recording of drilling data during the drilling process. This technique can be used for underground investigations to differentiate ground strata, detect the presence of fractures and voids, and evaluate geological features and mechanical properties of geomaterial. When MWD is used for geotechnical investigations, it can improve site characterization, identify variable conditions, improve design and construction, lead to shorter project delivery times, reduce the cost and risks associated with limited subsurface data and geotechnical uncertainties, and maximum return-on-investment. Given these benefits, MWD is gaining attention among transportation agencies and the geotechnical industry. Federal Highway Administration’s (FHWA’s) innovation deployment program “Every Day Counts (EDC-5)” includes the implementation of Advanced Geotechnical Methods in Exploration (A-GaME), which aims to implement effective, underutilized subsurface exploration methods, including MWD, in U.S. practice. This paper provides an overview of the MWD technology for geotechnical site investigations and presents a case history where MWD was employed to design deep foundation for the construction of a building in Massachusetts. The advantages of this technology for risk reduction and project cost and time saving are also discussed.

Oct 1, 2022

By L. D. Tracy

This is the third of the series of reports on coal-mine royalties and leasing conditions in Illinois. The results of the study of District VI were published as Serial No. 2726, January, 1926, and those of District VIII as Serial No. 2745, April, 1926, of the Bureau of mines. The counties of Macoupin, Sangamon, and Montgomery, which are three of the principal coal-producing areas in the northern part of District VII, have been chosen for this report because these counties cover an entirely different part of the State than do the two districts already covered. Some leases in, Randolph and Washington counties are included as they are in the southern part of the district, and the data happened to be readily available.

Jan 1, 1926

By Gerald T. Homce, James C. Cawley

Problem: CFOI and SOII data show that 2,287 U.S. workers died and 32,807 workers sustained days away from work due to electrical shock or electrical burn injuries between 1992 and 1998. Method: The narrative, work activity, job title, source of injury, location, and industry for each fatal electrical accident were examined. A primary causal factor was identified for each fatality. Results: Electrical fatalities were categorized into five major groups. Overall, 44% of electrical fatalities occurred in the construction industry. Contact with overhead power lines caused 41 % of all electrical fatalities. Discussion: Electrical shock caused 99% of fatal and 62% of nonfatal electrical accidents. Comprising about 7% of the U.S. workforce, construction workers sustain 44% of electrical fatalities. Power line contact by mobile equipment occurs in many industries and should be the subject of focused research. Other problem areas are identified and opportunities for research are proposed. Impact on Industry: Improvements in electrical safety in one industry often have application in other industries.

The Olympic Dam copper/uranium deposit was discovered in 1975 and subsequently commenced production in 1988 at a rate of 1.5 Mtpa using the sublevel open stoping mining method. In the following five years the operation underwent two optimisation programs that have increased mine output to the current rate of 3.4 Mtpa of ore. The pre-expansion requirements were annual development of approximately 10 000 m and the placement of around 500 000 m 3 /yr of cemented backfill. Previous to 1995 all hoisting was carried out by the Whenan shaft. The Robinson shaft was commissioned during that year to hoist increasing development mullock tonnages and to allow for increased ore hoist via the Whenan system. In 1996 WMC committed to expanding the output of the operation from 85 000 tpa (1996/97 budget) copper metal to 200 000tpa. The corresponding increase in mine ore production requires expansion to a nominal rate of 9.0 Mtpa. To achieve these increased tonnages, major hardware installations will include sinking of a third shaft capable of hoisting in excess of 9.5 Mtpa, a rail haulage horizon utilising automatic trains, expansion of the existing backfill plant to a production capacity of over 1.8 million m 3 /yr, increasing long term development rates to 15 000 m/yr and increasing the production drilling and blasting rates in line with the higher stope production output. This paper provides detail into the intended hardware (shafts, equipment, etc) of the mining system, and outlines the intended long-term operation and management of the operation. Of particular note is the background requirement of ensuring existing production targets are met to provide critical cashflows into the project during the period of expansion.

Jan 1, 1998