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By R. W. Carn, D. Vincent

Environmental Considerations With significant increases in bulk coal movements through terminals, operators are under constant social and political pressure to reduce or remove environmental pollution problems incidental to their operations. To meet these requirements, both equipment manufacturers and terminal designers are endeavoring to design equipment and systems with stringent environmental controls. The most challenging environmental problems facing coal terminal designers and developers are terminal siting restrictions, dust control, and noise abatement. Terminal Siting Finding a suitable site can be a difficult problem because of public concern over coal dust or the impact of a terminal on the surrounding community or natural habitat of the area. Often the only suitable flat land available for terminal development is on a tidal estuary or salt water marsh with great environmental value. In many cases a period of four to six years of full environmental and social assessment has been needed. A recent example of such difficulties is the expansion at Roberts Bank, British Columbia, where environmental impact assessment studies and their public review took almost six years from initial expansion applications until the time of approval. Dust Control Modern coal terminal dust control techniques usually consist of water sprays at strategic locations to suppress dust. The application points include rail car or barge dumper, main conveyor transfers, perimeter sprays around stockpiles, stacker/reclaimer, ship-loader transfers, and loading spout. The water sprays may include a chemical wetting agent or surfactant to reduce the water requirement and increase effectiveness. Recently there have been advances with development of effective micro foam agglomerating agents. In these systems, a micro foam with very small bubble sizes is sprayed into the coal stream. The foam fills the interstices between coal particles and wets the coal fines. These systems have proven to be very effective and usually one application before stockpiling and one upon reclaiming will markedly reduce the coal dusting. Stockpile perimeter sprays can be operated either manually or at the sophisticated terminal, actuated by a computerized control system that senses key environmental conditions such as humidity, precipitation, and wind velocity. Most modern terminals collect the drainage from the stockpile area, remove the solids in settling basins, then recirculate the water to reduce water requirements and effluents from the site. Dusting of long-term storage stockpiles can be reduced by spraying the piles with chemical resin or latex binding compounds to seal the surface. These compounds also can minimize erosion of the pile by rainfall. Dust collection with air evacuation systems and cyclone or wet scrubbers can be used at key areas such as rail car dumpers, main conveyor transfers, and ship-loader spouts. The trend in dust control is away from dust collection since most dust collectors are high maintenance items requiring good operator supervision and servicing. Coal handling conveyors are usually open and uncovered. However, in areas requiring special attention they may be covered or even completely enclosed. Dust generation from terminal roads is often a significant amount of the total dust emitted from a terminal. To reduce this dusting, roadways where traffic is heavy can be paved or sprayed by water trucks. Speed limits can be enforced and use of tracked mobile equipment for stockpile handling rather than rubber-tired loaders is encouraged by authorities. Noise Abatement Terminals located close to residential areas are often faced with noise control problems. Noise can be one of the most difficult environmental problems to solve. Usually, use of electrically-powered equipment is encouraged to reduce noise levels. Rail car dumper houses can be totally enclosed to reduce both dust and noise emissions. Diesel locomotives can be fitted with special muffling devices. Green belts of trees surrounding a terminal or the ap-

Jan 7, 1983

By R. J. Latino

Because of the lack of a universally accepted definition or standard for RCA, we are left to our own conventions in the marketplace as to what is most ?effective? or a ?Best Practice? for our own facilities or organization. This lack of uniformity in the application of RCA produces an equal lack of uniformity in the measureable outcomes of RCA on the bottom-line from site to site and industry to industry. What is the definition of success for an RCA? Is it regulatory compliance? Is it some quantifiable measure of bottom-line performance? Is compliance and bottom-line performance the same thing? Can we measure the ROI we receive by doing compliant RCA? These questions must be adequately addressed if any definition of RCA is to be effective on the bottom-line. Like our various Corporate Vision and Mission Statements, what would be our Vision and Mission for RCA? When pondering the answer to this question, we should consider: ? What Key Performance Indicators will the Success of RCA be Linked to? This provides a direct correlation to the corporate dashboard and therefore garners support for the RCA effort when implemented at the sharp end. Not until we know what KPI?s will effectively measure our maintenance and reliability objectives can we begin to establish which opportunities will afford the greatest returns1. ? What Bottom-Line Metrics will be Tracked to Measure the Effectiveness of Our RCA Effort? Will it be increased production, profitability, regulatory compliance, etc.? Will it be decreased injuries/fatalities, claims, customer complaints, risks, etc.? We should be specific about these metrics and their correlation to the metrics on our corporate dashboard. ? What Will Trigger an RCA Investigation? Normally companies will establish quantifiable thresholds to be surpassed before an RCA will be conducted. Examples may be an OSHA recordable injury, a failure event in which production losses exceed $250,000, an equipment failure in excess of $50,000 or a regulatory violation. This is the norm. However, we should realize this is using our RCA skills totally on a reactive basis. High Reliability Organizations (HRO) strive for proaction and they also use RCA proactively. Why can?t we use RCA to analyze why unacceptable risks from an FMEA are so high? It is perfectly applicable yet rarely implemented in this fashion.

Feb 27, 2013

By Christophe Bragard

The Los Angeles Metro Eastside Extension light rail project included a 1.5 mile underground segment, which consisted of twin 18'?10" ID tunnels, bored with two EPB-TBMs. One of the major project challenges after the completion of the bored tunnels was the excavation of six cross passages within alluvial geology below the water table and with low ground cover. Sequential excavation methods were employed and this paper details the design, ground treatment, support measures, and construction methods used to mine these cross passages beneath the congested urban streets of the City of Los Angeles.

Jan 1, 2008

By William M. Gleason

The war in Vietnam stretched into another decade, an American President was at the brink of impeachment, the earth was given its own day, twin tower monuments of American ingenuity were completed in New York and would stand high above the Manhattan skyline for 31 years. Inflation, oil shortages, low commodity prices and America’s 200th birthday were part of the decade — it was the 1970s. For the mining industry, the demands of the decade would be high and the challenges would be significant. Because of the many challenges that lined up in front of it, the mining industry was forced to work smarter and more efficiently. The industry also expanded its borders in search of new resources and struggled along with the rest of the world through a fuel crisis, inflation and a recession.

Jan 1, 2007

By S. E. Chetlin

In the mid-1970?s, the market value of tangible assets of S&P 500 companies far outstripped the value of intangible assets, including intellectual property (e.g., 83% tangible assets v. 17% intangible assets).1 By 2005, the picture was quite different. By that time and continuing to 2010, S&P 500 companies? market value of intangibles was about 80%, with tangible assets accounting for only 16% of market value.2 This swing highlights the importance in today?s world of understanding intellectual property rights and varying strategies and options for protecting them. This paper discusses intellectual property rights particularly patents and trade secrets, specifically: 1) types of intellectual property; 2) choosing the mode of intellectual property protection; 3) obtaining patent protection; and 4) using patents as a sword versus a shield.

Jan 1, 2012

By R. Switalski, M. Schafer, R. Pintabona, M. Kritzer, B. Lukajic, S. Janosko

Methane gas caused an eight-month shutdown of mining operations at the Mill Creek, Phase 3, Tunnel. The gas-related shutdown occurred as the tunnel was advanced to an approximate distance of 2,700 feet, which constitutes approximately18% of the total tunnel length. The construction of an emergency ventilation shaft, a comprehensive program of de-gassing wells and an expanded gas monitoring system were used to mitigate the gas condition. When complete, this tunnel will be utilized to convey and store combined storm and sanitary sewage collected from a portion of Cleveland, Ohio and ten suburbs. This paper will provide an overview of gas related remedial measures and explain how these measures were integrated into the project to ensure safe tunneling conditions.

Jan 1, 2007

By R. D. Begley

This paper will present detailed design drawings of a flexible single floor residential superstructure proposed for both longwall and room and pillar mining conditions. All efforts were made to provide an immediately available economical alter- native for future home builders on subsidence prone land. Based on this fact, a basement was not included in the design because additional costs and measures would be required to minimize cracking and leakage. A cost comparison with a traditional superstructure demonstrated that this would be a cost effective alternative. The criteria used to determine the design of the residential structure was as follows: 1. The appearance should not be different then a typical three bedroom residence; 2. Only commercially available devices and present architectural and engineering technology should be used to achieve the required "flexibility" of the super- structure; 3. The structure as completed would be capable of resisting a predetermined amount of vertical and horizontal movement; and 4. If the structure was to experience stresses beyond its capabilities, it could be easily removed from the foundation and releveled.

Jan 1, 1986

By M. D. Max, A. H. Johnson

INTRODUCTION Gas hydrates have considerable potential to be a major energy resource owing to their apparent abundance in Arctic regions and along continental margins throughout the world (Kvenvolden, 1988). Yet, the oil and gas industry has been slow to pursue this opportunity. The primary reasons for this are the large conventional reserve base for natural gas worldwide and the perception that gas hydrate will not be a viable resource for another twenty or thirty years. Gas hydrates are thus viewed as a potential resource for the distant future, but not a valid investment for the near term. This paper addresses both global gas markets and gas hydrate technology, and shows that the commercial development of gas hydrate could proceed rapidly enough to constitute a near-term energy resource. GLOBAL GAS MARKETS The proven worldwide reserves of conventional natural gas are truly enormous, totaling over 6,000 TCF according to BP (2004). Moreover, those reserves have nearly doubled during the past two decades and now represent 67 years of consumption at the current production rates of 80 TCF per year (Fig. 1). This reserve increase has occurred even as global production of natural gas has increased by 67% during the same two decades (Fig. 2). While declining conventional gas reserves are a concern in North America, especially in regions where established infrastructure exists to bring gas to consumers, large new discoveries continue to be made elsewhere in the world. Indeed, in many parts of the world (such as the Middle East and parts of West Africa), natural gas has been regarded as an essentially worthless byproduct of oil production or exists in stranded gas fields. Given this situation, pursuing unconventional gas resources that are inherently riskier exploration targets and more expensive to produce would appear to have little rationale from a business standpoint.

Jan 1, 2006

By S. Acar, M. Botz

Introduction In 2007, Newmont Mining Corporation will begin construction of a milling and cyanidation leaching circuit for the Yanacocha site in Peru. Ore to be processed in the circuit contains a relatively high level of cyanide-soluble copper, and as a result, leach solutions are expected to contain elevated levels of copper and WAD cyanide. As the means of controlling copper levels in leach solution, a circuit will be installed to precipitate copper sulfide from barren solution using sodium hydrosulfide. In addition, a circuit will be installed to recover cyanide from barren solution, with recovered cyanide to be returned to the leaching circuit and treated solution to be utilized as make-up in existing heap leaching facilities. As needed to support design of the copper precipitation and cyanide recovery circuits, pilot testing was conducted in 2005 to determine preferred operating conditions and evaluate the performance of the processes. This paper presents results from the pilot testing where 99% copper reduction was achieved and 95% to 98% cyanide recovery was achieved.

Jan 1, 2007

By M. F. Bradley, G. M. Schoen

The Magmont Mine, a 50/50 venture between Cominco American Incorporated (the Operator) and Dresser Industries, Inc., (Halliburton), is a metallic mining and milling facility in the new lead belt of Missouri. The mine is located approximately 100 miles southwest of St. Louis. Legislation passed in 1992 by the Missouri legislature requires all metallic mining and processing facilities to apply for a Metallic Minerals Waste Management permit (MMWM) for their waste facilities. Regulations were subsequently promulgated by the Missouri Department of Natural Resources (DNR). Cominco obtained a MMWM permit (MM-006) from the Missouri DNR in 1992.

Jan 1, 2001

By J. D. Morgan

Introduction In 1986, the US economy passed the $4 trillion mark. However, the value of domestically processed materials of mineral origin fell slightly to $240 billion. The value of metals produced from US ores was unchanged at $5.6 billion, as was recycled scrap at $4 billion, while the value of industrial minerals rose slightly to $17.9 billion. Consumer demand strongly affects mining and the US economy is relatively saturated with longlived products. Moreover, in recent years there has been a steady increase in consumer, mortgage, and federal debt, inhibiting new purchases of goods. Motor vehicles and housing are major traditional markets for mineral materials. However, the 242 million US citizens already possess 170 million licensed motor vehicles and 92 million dwelling units. In 1986, domestic motor vehicle production fell 3%, to 11.3 million units, while new housing starts rose slightly to 1.8 million units. Nearly all mineral commodities move relatively freely in world trade. As detailed in Figs. 1 and 2, in the last three decades world production of major mineral materials has greatly increased. At present, substantial excess productive capacity exists not only in the US but also in many other countries. Consequently, the US mineral industry is encountering increasing competition from other sources, along with increasing competition from newer, engineered materials. For example, US production of plas¬tics has risen from 900 kt (1 million st) in 1950 to 22.7 Mt (25 million st) in 1986 - on a volume basis significantly greater than steel. Plastics, too, are mineral-based materials, some 7% of petrochemicals going to their manufacture. 1986 saw increased calls for protection. But President Reagan, in his 1987 State of the Union Message and Economic Report to the Congress, reaffirmed adherence to a policy of free and fair trade. However, he stressed the need for increased efforts to open foreign markets to US exports and to increase competitiveness of US industry US imports of mineral-based minerals in 1986 were valued at $40 billion and exports at $24 billion. Strategic minerals As detailed in Fig. 3, imports supplied a significant proportion of total US consumption of several important materials, including many classified as "strategic and critical." There were no changes in stockpile policy during the year. Congress debated the President's 1985 proposals to reduce stocks of World War II-type materials and to focus more on high technology materials needed for the cutting edge of future military material. But no final action resulted. However, Congressional concern about apartheid in South Africa did result in increasing pressure to limit imports of South African minerals. Meanwhile, the National Critical Materials Council in the Executive Office of the President intensified its efforts to be better able to advise the President. The Defense Production Act provides authority for priorities and allocations, supply expansions, voluntary agreements, and

Jan 5, 1987

By S. Noll

Ventilation is an essential part of any underground mining operation. It provides fresh air for workers and machinery, keeps up an adequate mine climate and dilutes and dissipates noxious gases. Possible changes in the economic environment for mining in the future, e.g. increasing energy costs, will necessitate optimization of distribution of airflow within most mines. This paper discusses the scientific set-up for measurements as well as the behavior and influence of parameters of ventilation according to airflow distribution under consideration of technically possible set-ups of mine fans. This study was done in an underground mine with a flat seam room and pillar mining method.

Feb 27, 2013

By Z. A. Md-Nor

Risk management is an established loss-control methodology that has been applied successfully in many industries. Recently, interest in this structured approach has grown in the mining industry. The main objective of this research was to develop a risk-assessment process, which is a part of risk management, that can be used by the U.S. mining industry to more thoroughly characterize risks associated with haul truck-related fatalities. The assessment is based on historical data obtained from the U.S. Mine Safety and Health Administration (MSHA) investigation reports, which includes 113 fatal incidents that occurred from 1995 through 2006. The risk-assessment process used in this research involves the following basic steps: identification of the risks, risk analysis and risk evaluation. The preliminary hazard assessment (PHA) method is used in identifying and quantifying risks. Risk levels are then developed using a pre-established risk matrix that ranks them according to probability and severity. The resulting assigned risk value can then be used to prioritize control strategies. This paper is a part of a detailed study on risk assessment for equipment-related fatalities in mining sponsored by the Western U.S. Mining Safety and Health Training and Translation Center.

Jan 1, 2008

By Roozbeh Afzali

Designing an appropriate tunnel blasting pattern reduces the cost of rock breakage and subsequent operations such as loading, haulage and support of tunnels. For that reason, we developed a software that designs tunnel blasting patterns. Using this software, three different tunnel blast design models based on parallel hole cut, namely, Swedish, Konya and Energy Balance, were investigated and compared for a virtual tunnel. Accordingly, blasting patterns were designed, for different cross sections. The trend of parameters such as specific charge and specific drilling as functions of tunnel cross-section was determined for each model. Our results show that, in general, The Swedish model gives lower specific charge and specific drilling compared to other models.

Jan 1, 2008

Editor’s note: As usual, the June issue features an industrial minerals review. And some thanks are in order. Thank you to the industrial minerals annual-review editor, to the technical committees chair and vice chairs and to the authors of the individual commodity profiles. Jim Norman of GeoTrans Inc. is the industrial minerals annual-review editor. Lucy McCartan, US Geological Survey, was the chair of the SME industrial minerals technical committees. She also served as the vice chair for agricultural minerals. Other technical committee vice chairs were: •Gary Tomaino, Specialty Minerals Inc., ceramics and refractory materials. •Srinivas (Vas) Veeramasuneni, US Gypsum, chemical raw materials. •William Langer, US Geological Survey, construction materials. •Vanessa Santos, Independent, fillers and pigments. •Richard Berg, Montana College of Mineral Science and Technology, specialty minerals. Their help makes possible this June industrial minerals issue. On behalf of the readers, the editors thank them.

Jan 1, 2002

By Rajive Ganguli

There are several elements of online pedagogy and information technology that are being used in the University of Alaska Fairbanks’(UAF) course “ES 201: Computer Techniques,” to enhance classroom teaching. The use of information technology in this class grew from a desire to make lecture notes available to students. This has grown to include a sophisticated, online delivery software package. It provides chat rooms, discussion groups, and online testing and grading. Online delivery aside, the class uses the telnet, e-mail and C++/FOR-TRAN compiler facilities of the university server during class to enhance learning. During class, for example, the students read the lecture notes on the Web browser, telnet to their university Unix accounts, check their e-mail and download programs (to be covered in class) sent by me, and then compile, run and modify the programs. The class, therefore, requires students to be active most of the time. This ensures their full attention and better learning due to the hands-on experience (Fig. 1).

Jan 1, 2000

By S. Hamilton

Borates are essential to life, and to many products that are essential to an acceptable standard of living. They occur naturally in seawater at an average concentration of five milligrams of boron per liter. Fresh water lakes, rivers, streams and ground water generally have concentrations of about one milligram boron per liter. Borates are also present in soil at concentrations ranging from 0.1 to three milligrams of boron per kilogram. Because most of that boron is locked into insoluble minerals, clay or organic matter, boron deficiency is more widespread than boron enrichment. Borates evaporate into the atmosphere from seawater, rain, snow and hot springs. In rain and snow, natural boron concentrations range from 0.002 and 0.1 milligrams boron per liter. All told, boron moves through the atmosphere at a rate of 5 Mt to 7 Mt/a (5.5 million to 7.7 million stpy).

Jan 1, 2005

By Y. Wang, E. Forssberg, A. Johansson, B. Chan

A super-conducting high gradient magnetic separator with matrix vibration in dry separation mode is a powder purification device, which has been used to remove weakly magnetic impure particles from fine calcite powders below 53 µm in this study. A fundamental question concerned is the evolution of the matrix clogging under gas-solids loads. This paper presents the improvement of the separation selectivity using a method of mechanically based vibration on the matrix in the separator. The functions of the matrix vibration are discussed. The results indicated that the mechanically based vibration on the matrix within a high intensity magnetic field while a feed was introduced in an air stream, was found to be effective for the dry purification of fine powder materials.

Jan 1, 2001

By D. Dimitriadis, T. Polglase, W. Phillips, R. Jenny, M. Botz

Cyanidation processes for the extraction of gold or silver frequently involve the processing of sulfur-containing solids which react with cyanide to form thiocyanate. The formation of thiocyanate is an undesired side-reaction, and in many cases thiocyanate formation results in a prohibitively high cyanide consumption. With the increasing number of gold and silver mining projects which involve the processing of sulfide ores or concentrates or which utilize a biological sulfur oxidation process, more attention has been focused on minimizing thiocyanate formation and in treating solutions to eliminate toxicity associated with thiocyanate. Though not yet commercially applied, there are several technologies available to recover cyanide from thiocyanate to both reduce tailings toxicity and allow the reuse of cyanide otherwise lost to thiocyanate formation. This paper presents an overview of technologies available for recovering cyanide from thiocyanate along with estimated operating costs for the technologies. Pilot testing data suggests that in some cases, cyanide can be recovered from thiocyanate for approximately the same cost as newly purchased cyanide.

Jan 1, 2000

By J. E. Bernick, J. Davies

This paper describes the design and construction of a 22.86 m (75 ft) long jacked tunnel, which was successfully installed, despite difficult mixed face conditions at Metro-North’s Westport Station, in Connecticut in the fall of 2003. The tunnel utilized what is believed to be, the first application of a steel grillage system within the United States. This grillage was installed before the jacking started and allowed the tunnel to be jacked under four live railway tracks, which included the Acela high speed line, without affecting train operations. The clearance between the top of the tunnel and the rails was only 0.9 m (3 ft).

Jan 1, 2005