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By F. D. Fox

The Flambeau and Ridgeway Mines, both owned and operated by wholly owned subsidiaries of Kennecott Minerals Company, were located very close to populated areas having initial concerns about health, safety and the environment. The success of both operations depended upon developing a framework of community support and enhancing sustainable development opportunities throughout the entire life cycle of the mining operations to address these concerns. The protection of the Flambeau River was the cornerstone of the Flambeau Mine’s success. The highest priority for the Ridgeway Mine was to ensure long-term physical, chemical and ecological stability of the reclaimed mine site. Both of these goals have been achieved and are discussed in this paper, which highlights Kennecott Minerals Company’s integration of sustainable development principles into its business decision-making and management processes.

Jan 1, 2003

By M. H. Dunn, T. P. Danehy, C. F. Denholm, S. L. Busler

The problems associated with abandoned minelands are so extensive that neither federal, state, or local governments nor the mining industry nor watershed groups can adequately address these problems individually. By combining talents and resources, however, these problems are being solved efficiently, effectively, and economically. Utilizing existing water monitoring data, local public-private partnerships have successfully designed and built passive systems within five weeks to six months which treat discharges up to hundreds of gallons per minute that vary in quality from net alkaline to highly acidic, containing as much as 200 mg/L dissolved iron and 70 mg/L dissolved aluminum.

Jan 1, 2002

By Henry A. Signore

The Appalachian coalfield, located in eastern Kentucky, Pennsylvania, Virginia and West Virginia, has been one of the most productive in the United States. Total production from the Appalachian coalfield during 1994 was 340.8 Mt (375.4 million st), or 37% of the 929 Mt (1 billion st) produced in the United States that year. This region contains various coal types from high- to mid-sulfur coal in Pennsylvania and northern West Virginia to low-sulfur, compliance steam coal and premium-grade metallurgical coal in eastern Kentucky, Virginia and southern West Virginia. The region's product is in high demand in domestic and export markets. Productivity continues to improve, resulting in the primary coal operators solidifying their market positions.

Jan 1, 1995

By S. J. Jung

The most frequent causes of accidental injury and fatality are carelessness and ignorance; and the most common accidents are haulage accidents, fall, drowning, and fire. However, in this modern day and age, severe injury has become the dire consequence of an ever-increasing number of industrial and mining accidents as well as sport-, military- , etc. Mine accidents have declined dramatically in number and severity through decades of research, technology, and preventive programs. However, preventing recurrence of disasters like those of the past remains a top priority requiring constant vigilance by management, labor, and government. The goal of the present research is to investigate and identify root causes associated with types of mining accidents (victim being caught by an equipment, bodily motion, over exertion, etc) and nature of injuries such as (sprain and strains, fracture, dislocation, amputation, etc). Further, we hope to discover the impetus of the root causes occurring more and more often in this modern day of technology and quality awareness. With the different dimensions of accidents and injuries brought into the fold, there is the need for researchers and mining operators to comprehend and better still visualize significant patterns of associations among these variables of interest. We assume that, there is a high correlation between many dimensions of nature of injuries and types of accidents. This suggested a principal component analysis to reduce the dimensions for easy and amenable interpretation.

Jan 1, 2012

By Lane White

Refractory gold ores are those from which a significant percentage of the gold cannot be recovered by conventional cyanidation. Historically, roasting has been the primary method for rendering such ores amenable to gold extraction; however, roasting creates environmental problems that are not acceptable in many locations. During the 1980s, consistently strong gold prices drew increasing attention to refractory gold ores, and new processing schemes were commercialized, most prominently aqueous pressure oxidation and more recently bacterial oxidation. Since 1985, pressure oxidation has been incorporated into four plants processing refractory gold ores. A fifth plant is scheduled for start-up in early 1990, and three additional plants are scheduled for production before late 1992. A technical session on treatment of refractory ores was included in the program of `World Gold '89, a Gold Forum on Technology and Practices' held by SME and the AusIMM in Reno, NV, Nov. 5-8, 1989. This article summarizes material from five of the papers presented during the refractory gold session and published in the proceedings of `World Gold '89,' edited by Roshan Bhappu and Rod Harden. The complete proceedings are available from SME Publications Sales, P.O. Box 625002, Littleton, CO 80162-5002 $53.50 for members, $38.50 for student members, and $73.50 list price.

Jan 1, 1990

By Lane White

The 1989 Annual Meeting and Exhibit of SME in Las Vegas, NV, February 27 - March 2, 1989, was the largest ever, drawing more than 4000 regis¬trants and 240 exhibit booths. Technical sessions included presentation of nearly 500 papers, including symposia on Biotechnology in Minerals and Metals Processing, Surplus Capacity in the International Metals Industry, and APCOM `89 - the 21st International Symposium on Application of Computers and Operations Research in the Mineral Industry. Technical sessions covered the gamut of minerals industry interests; however, the proximity of the meeting to recently surging gold development in Nevada drew special attention to gold operating practices. Several of the papers on gold processing are reviewed below. To keep pace with the strong world- wide interest in gold development, SME has scheduled three additional upcoming programs that will focus specifically on gold: World Gold '89 - Gold Forum on Technology and Practices will be held November 5 - 8, 1989 in Reno, NV, as a joint meeting and exhibit between SME and the Australasian Institute of Mining and Metallurgy. Technical sessions will encompass a full program of papers covering geology and exploration, mining, and mineral and metallurgical processing. Cooperating sponsors for this meeting include the Canadian Mineral Processors Division of CIM, The Institute of Metals, The Institution of Mining and Metallurgy, The Mining, Geological & Metallurgical Institute of India, and The South African Institute of Mining and Metallurgy. Gold '90 - Salt Lake City, UT, February 26 - March 1, 1990, will be a symposium held in conjunction with the 1990 SME Annual Meeting. Current research on the processing of refractory gold ores will generate innovative papers on process mineralogy at this symposium, with special emphasis on gold with pyrite and gold with carbon. Other sessions are planned for gold exploration and mining, gold metallurgy, gold plant design and practice, and gold in scams. Advances in Gold and Silver Processing Conference, October 1 - 3, 1990 will be held in Reno, NV. Preliminary planning calls for technical sessions on heap leaching practice, refractory ore processing, non-traditional lixiviants, bioleaching, metal recovery from solution, and the environmental aspects of processing operations. PLANT DESIGN, OPERATION Technical sessions organized by the Minerals and Metallurgical Processing Division of SME at this year's meeting in Las Vegas covered a wide range of gold operating practices. Eight papers relating to gold plant design, operation, and equipment are summarized here. Preprints of these papers are available by writing to Publications Sales, PO Box 625002, Littleton, CO 80162-5002 ($2.50 per paper for AIME members, $4 for nonmembers). Continuous elution process A. M. Stone, of Bechtel Australia Pty. Ltd., described the "Development of the Continuous Elution Process for Extraction of Gold from Carbon" (pre-print 89-75). Developed by Bechtel Pacific Corp. for Ok Tedi Mining Ltd., the Continuous Elution Process uses the same reagents as batch processes for elution of gold from carbon, while yielding significant savings in stripping vessel size and energy consumed in comparison with equivalent batch processes. The process is also simpler to operate than batch processes. Other advantages include reduced maintenance costs, higher average eluate grade, and near steady final eluate grade. Pilot testing for the Continuous Elution Process was conducted at Western Mining's Kambalda gold plant beginning in December 1982. The Continuous Elution Process is a continuous countercurrent system operating in a pressure vessel at elevated

Jan 1, 1989

By Wern-ping (Nick) Chen

The Florida Department of Transportation District 6 (FDOT D6) began a study in 1987 for a master plan to improve the traffic circulation and congestions between the Port of Miami (POM) and downtown Miami, FL. This study included a tunnel connection between two man-made islands, the Watson and the Dodge islands. Though a finding of no significant impact (FONSI) was completed in 1992, the project remained on hold for about 10 years. In 2002, Florida Turnpike took over this project, re-evaluated its benefits to the lo-cal communities, determined its feasibility (specifically the tunnel options) and established a probable cost. In 2005, the FDOT D6 regained its charge over the project and concluded that a bored tunnel under Biscayne Bay is feasible. Its primary components are: ? Widening of the MacArthur Causeway Bridge, to accommodate truck traffic to the Port of Miami. ? A tunnel connection between Watson Island and Dodge Island, where the POM is located. ? Connections to the POM roadway system, either for the traffic from the city of Miami or for the truck traffic from I-395 to the POM. The project will improve access to and from the POM and provide a dedicated roadway connector linking the POM with the MacArthur Causeway (State Route 41/1) and I-395, specifically for the trucks in and out of the POM without going through downtown Miami. As identified in the project information memorandum (PIM), its primary objectives are to: ? Improve access to the POM, helping to keep it competitive and ensuring its ability to handle projected growth in its cruise and cargo operations. [ ] ? Improve traffic safety in downtown Miami by removing POM traffic, trucks and buses from the congested downtown street network and, in doing so, facilitate ongoing and future development plans in and around downtown Miami.

Jan 1, 2009

By P. Fauvel, V. Nasri

In January 2001, French and Italian governments signed an agreement for the construction of a new Lyon-Turin railway line. This project includes a tunnel of 53.1 km length and a maximum of 2500 m overburden to be designed for a reference speed of220 km/h. The tunnel crosses major part of the West Alpine geological formations, which are very complex and contrasted in terms of the nature of rocks and the mechanical and hydrogeological conditions. In addition to the twin single-track tubes, numerous intermediary shafts, security station and intervention sites and cross passages should be built to respond to the security, operational and construction requirements. This paper describes the results of the preliminary engineering design and multiple challenges of this very long and deep railway tunnel.

Jan 1, 2005

By Tuncel M. Yegulalp, Anuta Belova

This paper expands on the ZECA (Zero Emission Coal Alliance) technology, which is aimed at making coal a sustainable source of clean energy in the near future. The technology proposed immediate capture of carbon dioxide and other pollutants upon generation, thus alleviating their negative effects in the Earth’s atmosphere. ZECA proposes using chemical energy of coal to produce hydrogen; the latter is then used to produce electricity via fuel cells or Hyrogen-Oxygen turbines. In this study, a chemical engineering package, AspenPlus 12.1, is used to simulate the reactor (reformer) in which hydrogen is produced from methane water and lime as part of the zero emission power plant. Thermodynamic conditions, pressure and temperature, are optimized with respect to molar hydrogen production. Under the proposed conditions, molar conversion efficiency, carbon to hydrogen, of 95% is achieved. Further studies are required to model the complete power plant and to optimize it for efficiency.

Jan 1, 2005

By J. Jeffrey Wagner, Michael J. Bailey, Peter M. Douglass

The Chambers Creek Interceptor Sewer Tunnel project consisted of 2-1/2 miles (4 kilometres) of nominal 9-foot (2.7-metre) O.D. tunnel driven through predominantly glacially overridden soils. Mole-Collucio Construction Company initially elected to drive the entire tunnel with a Lovat TBM. However, this machine could not control the fast raveling ground conditions which developed when the TBM encountered sands overlying very dense, hard glacial till or boulders. As a result, a shield and digger machine was brought in for a 1700-foot (518-metre) long segment. Pumped wells spaced roughly 50 to 125 feet (15 to 38 metres) apart were utilized to dewater about two-thirds of the alignment during construction. Initial support consisted of steel ribs and wood lagging, with a final lining comprised of pre-cast concrete pipe segments grouted in place.

Jan 1, 1985

By A. Moergeli

The Swiss are currently building the world’s longest tunnel, the 35-mile long Gotthard Base Tunnel. At Sedrun, for the first time in tunneling, four Roadway Support Machines will drive through most difficult ground, supporting variable diameters of up to 13 m. The machines are prepared for their first deployment. At Amsteg, two Hard Rock TBMs have successfully crossed a known fault zone by applying full circle steel arches and shotcrete immediately behind the cutter head. Comparisons between Drill& Blast and Hard Rock TBM are shown.

Jan 1, 2005

By J. J. Carlson

Studies were carried out to determine whether filtration rate changes observed in an iron ore concentrator were due to variations in particle shape. It was confirmed that ores mined from different locations differed in filtration rates by as much as 60%. However, when image analysis was used to quantify the shapes of the individual particles in the filtration feed, it was found that the particle shapes showed almost no variation, and the shapes did not correlate with the filtration rate. It was also determined that the filtration rate variations were not caused by changes in particle size distribution. These results suggest that the differences in filtration rate are due to factors other than size and shape, such as surface chemistry.

Jan 1, 2008

By Antoni Kalukiewicz

From 1997 through 2000, a team of Polish experts headed by the author studied the prospects of mining newly discovered emerald deposits in Afghanistan. This article describes the scheme for mechanization of the mining operations, along with improvements made to the ventilation facilities and lighting. The required equipment was flown to Afghanistan and the Afghan miners were trained in machine operation and maintenance.

Jan 1, 2005

By Malcolm D. Flavel

Much has been said and written about the world's, and particularly the united states of America's, energy crisis. The relative changes between cost components of production have altered because the days of cheap energy have now gone. Decisions that made capital investment reduction attractive to treat large tonnage lower grade ore bodies appear to be no longer valid because average energy costs for comminution that were less than 1 cent per kilowatt hour in 1972, are now more than 3 cents and will shortly become 6 cents according to some projections. Increased capital investment to improve processing energy efficiencies are certainly going to be pursued. Energy today is the largest cost component in the average mineral production facility. It takes more than 12000 kilowatt hours to produce one ton of finished steel and more than 60000 kilowatt hours for each ton of copper and aluminum.

Jan 1, 1980

By Dermot Winters

The Surface Mining Control and Reclamation Act (SMCRA, or the Act) was enacted on August 3, 1977. The Act was written, in part, to put an end to uneven environmental standards and to establish minimum national standards. Certainly, one of the motivating factors for passage of the Act was the success of the Federal Coal Mining Health and Safety Act of 1969 in reducing deaths and injuries in the coal industry nationwide. Section 516 (b) (1) of the Act requires *that subsidence be prevented from causing material damage to the extent technologically and economically feasible except in those instances where the mining technology requires planned subsidence in a predictable and controlled manner. Section 516 (c) of the Act authorizes the regulatory authority to suspend underground mining if there is imminent danger to inhabitants of urbanized areas, cities, towns, and communities. On December 13, 1977, the interim program, which applies a portion of the performance standards of the Act, was promulgated. Then on September 18, 1978, the proposed permanent program was published for public comment. Finally, on March 13, 1979, the final permanent program was promulgated and the States were given a period of time to submit their programs for approval.

Jan 1, 1986

By K. Kohli

A case study involving a historic structure undermined by longwall mining is presented in this paper. The location of this study is in South Western-Pennsylvania; USA. The structure is 150-years old and subsided 4.5 feet. This paper discusses the mitigation measures taken to reduce the subsidence damage and its effectiveness.

Jan 1, 2002

By V. K. Kollipara

Air flow patterns in the face area of a room-and-pillar mining are critical for understanding the dust dispersion characteristics and for developing engineering controls. SIUC has previously performed a CFD study to analyze the airflow patterns in the face area when continuous miner is making a straight cut. Results from this study identified low air velocity and re-circulation zones in the face area and illustrated the significance of line curtain, and scrubber operation on the air flow patterns. This paper discusses similar analyses when continuous miner is making a right turn cut as it is considered to be the dustiest cut among all the cuts made to advance an entry through a crosscut. This paper presents results for box-cut development for a right hand turn x-cut. This paper also addresses line curtain advance and air leakage through the curtain on the airflow patterns in the face area for such a cut. Low air velocity and recirculation zones were identified by analyzing the velocity vectors.

Jan 1, 2012

By Matthew E. MacGregor, Hugh T. Kelly

I.H. 635 (LBJ Freeway) was constructed as a loop freeway around the city of Dallas in the late 1960s and early 1970s with a design capacity of 160,000 vehicles per day (vpd). Today’s facility is carrying over 270,000 vpd. To help mitigate community concerns with regard to right-of-way issues, noise, safety, and traffic disruption, the Texas Department of Transportation (TxDOT) is planning a number of significant improvements. The West Section improvements include the construction of managed HOV/Toll lanes. Within this 8-mile section, TxDOT is planning two mined tunnels(1.5 and 1.9 miles long) beneath the LBJ Freeway. The mined tunnels will connect to cut-and-cover box sections in both the east and west directions. This paper presents an overview of the project development from the design schematic, through the geotechnical investigations, into the current design stage. The project is being planned for implementation by use of a Comprehensive Development Agreement.

Jan 1, 2005

By T. L. Owen

Since 1993 Cyprus Amax has brought $2.5 billion dollars of greenfield and expansion projects into production, taking it from a mid-sized domestic minerals company into a major international minerals organization. The near simultaneous development of these multiple mineral projects in different locations around the world provided the opportunity for Cyprus Amax to develop a formal project management approach based, in large part, on an outsourcing philosophy. This formal project management system along with its outsourcing philosophy has served the growth agenda of Cyprus Amax extremely well. These preceding factors, coupled with the in-house retention of a core project group that fully understands the breadth of skills and abilities needed to undertake development of multiple large projects successfully, have been the cornerstone of Cyprus Amax’s project development success.

Jan 1, 2000

By H. K. Lin

Deepwater discharges of sulfide flotation tailings have been practiced for several decades. Oxygen penetration and organic matter content in such environments are the two major factors that determine their reduction-oxidation condition and hence the rate of sulfide mineral dissolution under such discharge environments. In this study, the effects of solution redox potential and pH on the dissolution of some heavy metals from sulfide flotation tailings were examined. Zn, Pb and Cu concentrations in solution were all higher at a higher redox potential and lower pH. Dissolved Zn concentrations reached 100 ppm even at a low redox potential of 105 mV and near neutral pH after 33 days. Pb concentrations were below 2 ppm at 105 mV and near neutral pH after 165 days. At 105 mV, the Cu concentrations were below 0.2 ppm at near neutral pH after 165 days. At pH 2.3, the Fe concentrations were higher at 420 mV than at 105 mV. But at pH 6.8, the Fe concentrations were lower at 420 mV than at 105 mV, due to the oxidation of Fe2+ to Fe3+ and the subsequent precipitation of ferric hydroxide. Arsenic concentrations in solution were all less than 0.002 ppm. For Zn, Cu and Fe, no significant differences were observed between the tests in solutions prepared using seawater and those using distilled water. However, Pb concentrations reached higher levels in solutions prepared using seawater.

Jan 1, 2009