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The 22nd Annual American Mining Hall of Fame Awards Banquet sponsored by the Mining Foundation of the Southwest will be held at the Westin La Paloma in Tucson, AZ on Saturday, Dec. 4, 2004. This year’s inductee, guest of honor and featured speaker at the banquet will be J. Steven Whisler, chairman and chief executive officer of Phelps Dodge. Whisler is also a director of Phelps Dodge, Burlington Northern Santa Fe, America West Holdings, the National Mining Association, the International Copper Association and the Copper Development Association.

Jan 1, 2004

By Z. T. Bieniawski, José Miguel Galera, Benjamín Celada

TBM case histories from over 400 tunnel sections are analyzed presenting a comprehensive application of the Rock Mass Excavability (RME) index (Bieniawski et al.2006). The paper introduces two new adjustment factors, called the Factor of Tunnel Length and the Factor of Crew Effectiveness, which were established to represent more realistically the interaction of the rock mass characteristics, the TBM parameters and the performance of the crew operating the machine. A new correlation is provided for predicting the average rate of advance of double-shield TBMs working specifically in the double-shield mode.

Jan 1, 2007

By Paul Gribbon, Julius Strid, Greg Colzani, Jim McDonald

Portland, Oregon’s $370 million West Side Combined Sewer Overflow Tunnel Project has completed the final phase of construction and commissioning. The construction contract, which began in September 2002, was a reimbursable cost plus fixed fee contract that followed a qualifications-based contractor procurement process and apre-construction planning phase. This paper addresses the final results of the contracting method and provides a lessons-learned case history. Specific items addressed include the benefits realized from the contracting method, areas of improvement, final costs compared to the original contract estimates, design changes and schedule impacts, and subcontract management issues.

Jan 1, 2007

The extraction and processing of minerals from surface mines and quarries can produce significant fugitive emissions as a result of site activities such as blasting, unpaved road haulage, loading, primary crushing and stockpiling. Uncontrolled fugitive dust emissions can present serious environmental, health, safety and operational issues impacting both site personnel and the wider community. Simulation technology is finding increasing use for the purposes of advanced warning of potential problem emissions in addition to providing a basis for future planning applications where demonstrable compliance with regulatory requirements are necessary. The initial re-entrainment and subsequent dispersion of fugitive dust presents a process complicated by the combination of the in pit topography, the surrounding natural topography and the dynamic nature of emissions from these sites. These factors impact upon the accuracy and reliability of the conventional Gaussian plume based computational prediction methods employed for regulatory compliance and IPPC applications. This paper proposes that optimal modelling of open pit emissions may be more accurately achieved by the use of a multi-scale predictive modelling approach utilizing computational fluid dynamics (CFD) methods for high resolution near source dispersion and conventional Gaussian based methods for far field dispersion modeling. This paper presents a numerical based flow and dispersion analysis of a typical UK based open pit utilizing CFD in conjunction with a conventional Gaussian plume based methods. Typical operating emissions and meteorological conditions are obtained from long term data records collected at a large operating quarry extraction operation in the UK. Emissions are modelled using a Lagrangian framework within conventional atmospheric boundary layer (ABL) profiles expressed as functions of turbulence and velocity parameters under assumed neutral conditions. Results are presented in terms of the impact of site topography on in pit retention as compared to the Gaussian based method.

Jan 1, 2009

By Paul Hewitt, Tim Smirnoff

Design and construction of the Epping to Chatswood Rail Line tunnels in Sydney, Australia required an innovative approach to define hydrogeological properties of the Sydney Hawkesbury Sandstone and provided an insight into the hydraulic behaviour of fractured sedimentary rocks. To meet restrictive water inflow and infiltration criteria both the pre-treatment of zones of fractured or highly jointed rock, and waterproofing using an interior spray on membrane for the finished drained tunnels and stations was required. Methods typically used to address the interaction of groundwater and tunnels in the Sydney Basin are demonstrated by case histories from major design-build tunnel projects.

Jan 1, 2005

By Faruk Oksuz, Clay Haynes, Miguel Sanchez, Patrick Finn, Roger J. Maurer

The Milwaukee Metropolitan Sewerage District’s (MMSD)’s challenges of basement flooding and wet weather sewer overflows are being creatively addressed with the Northwest Side Relief Sewer tunnel. The $132 million, 20-foot diameter, and37,740 feet long conveyance and storage tunnel excavation in dolomite at depths reaching 165 feet below ground surface has been successfully completed within13 months in April 2004. This paper includes Owner’s perspective on the overall project, and the design and construction details by the Designer and the Contractor. The project contract documents included a comprehensive Geotechnical Data Report and the Geotechnical Baseline Report.

Jan 1, 2005

By Richard A. Cubeta

Precast concrete segments have been used in sanitary sewer tunnel design for decades. Federal mandates (reduction in heavy metals and I & I), and system design changes (increased retention times) and other factors have exacerbated corrosion problems. In an effort to combat the ever-growing effect of microbiologically induced corrosion, owners, engineers, and designers have been specifying thin-film lining systems to protect precast concrete segments. These systems have compatibility and installation issues. Chemical additives or calcareous aggregates have been utilized in precast concrete, but have only proven to retard the rate of corrosion and do not eradicate the problem. Solid cast polymer segments are stronger than precast concrete, do not require linings or coatings, are impervious to ground water infiltration, and, above all, are inherently corrosion resistant through and through.

Jan 1, 2008

Minerals are fundamental to the U.S. economy, contributing to the real gross domestic product (GDP) at several levels?mining, processing and manufacturing finished products. The estimated growth rate for the real GDP of the United States was 2.1 percent and the nominal GDP was about $13.8 trillion in 2007 (Table 1). The prime interest rate decreased to 7.25 percent in December from 8.25 percent at the beginning of 2007, reflecting actions taken by the Federal Reserve Board to counter financial difficulties surrounding subprime mort-gages. Delinquencies on subprime mortgages increased throughout the year, affecting not only the delinquent home owners but also financial instruments invested in mortgage-backed securities. The average contract mortgage rate for the purchase of previously occupied homes in the United States was 6.35 percent in November; a slight decrease from 6.37 percent in January but still greater than 5.34 percent reported in July 2003, the lowest rate in the past five years. With the tightening of credit, the seasonally adjusted annualized rate for new privately owned housing starts declined 27 percent from December 2006 to November 2007. The loss in the residential market was balanced by a 9-percent increase in nonresidential construction between January and August 2007, during which slight increases occurred in nearly all

Jan 1, 2008

By Thomas J. Kuli, Tim Rape

When a fan or blower breaks down or becomes worn, customers have two choices. They can replace it or they can have it repaired. In the past, replacement was the preferred option, especially when the equipment was severely damaged or worn. Now, however, customers are discovering the benefits of repairing or rebuilding. Even when the cost of repair is more than 60 percent of the cost of a new fan, customers are choosing the repair option. The cost savings can range from 20 percent to 80 percent. In many cases, the quality of the repaired part or component will exceed the quality of the original. This is because repair engineers have an advantage over the original designers. They can see how the existing fan performed — or failed to perform — in a specific application.

Jan 1, 2005

Nautilus Minerals and Neptune Minerals are betting that the next great metals rush will take place more than 1,500 m (5,000 ft) below the sea. Nautilus is the first company to commercially explore the ocean floor for gold and copper seafloor massive sulfide (SMS) deposits. Its main focus is the Solwara 1 Project, a polymetallic copper, gold, zinc, silver deposit that is under 1,600 m (5,200 ft) of water off the coast of Papua New Guinea in the western Pacific Oceans? Rim of Fire. Nautilus Minerals, in a joint venture with Placer Dome (now Barrick Gold), began its exploration of what would become the Solwara 1 area in 2005 with side scan sonar and dredge sampling. The dredge and grab sampling confirmed the grade tenor of earlier sampling by scientific research programs. The 45 dredge samples aver-aged 10.8 percent copper, 3.7 percent zinc, 224 g/t (6.5 oz/st) silver and 13.7 g/t (0.4 oz/st) gold. Nautilus has since staked out more than 300,000 km2 (115,800 sq miles) of tenement licenses and exploration applications in the waters off Papua New Guinea, Fiji, New Zealand, Tonga and the Solomon Islands. That is an area about the same size of the United Kingdom. Interest in Nautilus and its projects has grown tremendously since its inception. The company is now listed on the Toronto Stock Exchange. It has raised more than $300 million and spent more than $23 million on exploration. The company has gained the backing of mining majors such as Teck Cominco, Epion, Anglo American and Barrick Gold. It is positioned to become an emerging producer in 2010. Teck Cominco recently agreed to exercise share purchase warrants to acquire three million additional common shares of Nautilus at a price of US$15 million. This will take Teck Cominco?s shareholding to approximately 7.2 percent of the issued shares. Teck Cominco will conduct and manage a ship-based exploration program that will run in addition to the exploration that was already planned for 2008.

Jan 1, 2008

By Darrell Gillis

Recent accidents in the United States underground Coal Mines and the on-going carnage in Underground Chinese Coal Mines has shown the danger associated with the lack of communication infrastructures in an underground environment. The US Mine Safety and Health Administration (MSHA) have introduced legislation that states all Underground Coal Mines must have two-way voice and personnel tracking capabilities by 2009. If Coal Mining companies are being forced to deal with this problem Tunneling Companies will not be far behind. This paper will examine current practices and best case technology to deal with these issues.

Jan 1, 2007

By Allan Sylvester, Paul E. Gabryszak, Diane R. Hirsch, David P. Field

With construction of the first phase of the Automated People Mover (APM) Tunnels nearing completion, this paper will address how knowledge from recent Tunnel Boring Machine (TBM) and New Austrian Tunneling Method (NATM) tunnel construction at the airport was used to refine the methodology for the next phase of tunnels currently in design. The benefits include an enhanced understanding of the ground conditions; allowing optimization of excavation sequences and support requirements; a more effective instrumentation and monitoring program; and improved construction details and related contract provisions.

Jan 1, 2007

By Morteza Gharouni Nik

Flexible Dilatometer Test (FDT) is one of the in-situ test methods for determining the deformational characteristics of rock masses. In this study, several dilatometer tests have been conducted in different geotechnical phases of site investigations by means of two types of FDTs. The purpose of this paper is comparison of the performance of these two types of dilatometers and analysis of the differences in the results of the tests.

Jan 1, 2008

By Bruno Bussière, Michel Aubertin, Anne-Marie Dagenais, Johanne Cyr

A five steps remediation program was commissioned in 1998 for the acid generating Lorraine mine site, located in the Témiscamingue region, Quebec, Canada. It included, as the main expenditure, a cover with capillary barrier effects (CCBE) used to limit oxygen migration. After construction of the cover, instruments were installed on site to monitor the CCBE performance. Modified oxygen consumption tests were also done to measure the oxygen flux through the cover. Results from water content and suction data, measured from 1999 to 2003, show that the capillary barriers effects are effective and that the water retention layer stays near saturation throughout the years. Oxygen fluxes estimated from monthly water content measures are generally below 10 g/m2/year. Results from modified oxygen consumption tests made on the site give almost similar oxygen fluxes. A two dimension numerical model of the Lorraine mine site was also constructed to verify that mathematical models could predict realistically the in situ conditions on such a large scale site. Numerical results obtained for three years show a good concordance between measured and calculated values. The results obtained form these different evaluation methods for the performance of a CCBE concur and confirm the efficiency of this cover in limiting acid mine generation.

Jan 1, 2005

By S. Krukowski

Iodine is a bluish-black, crystalline solid with sub-metallic luster, and has a specific gravity of 4.93. It volatilizes (sublimates) at ordinary temperatures into a blue-violet gas that has an irritating odor. Iodine is the least active of the halogens, all of which readily displace it. Only slightly soluble in water, iodine also dissolves in carbon disulfide, carbon tetrachloride and chloroform, giving a deep violet solution. The primary sources for iodine production are sub-surface brines associated with petroleum and natural gas deposits, and as a byproduct from nitrate deposits in Chilean desert caliche. The largest source of iodine is seawater which contains 0.05 ppm, or about 31 Mt (34 million st). Seaweed of the family Laminaria can extract and accumulate up to 0.45 percent iodine on a dry basis. Seaweed was an important source of iodine prior to 1959. However, it remains a significant source of iodine in the diets of many populations throughout the world.

Jan 1, 2005

By Zephaniah Varley, Satoshi Akai, Richard Sage, Steve Redmond, Mike Murray, Rohit Shetty, Gerald Skalla

One would be hard pressed to find another project as complex as this one given its configuration, the variety of issues to address and the required construction techniques. Contract C710 is currently under construction as part of Sound Transit’s Link Light Rail, connecting downtown Seattle with Sea-Tac Airport. The paper describes the construction-to-date of the deep mined station under Beacon Hill using the Sequential Excavation Method (SEM). This deep “binocular” station is being mined through some of the most challenging soft ground conditions in the USA. The excavated volume of the station is approximately 60,000 cy (46,000 m3) and the station comprises a variety of geometries and cross sections ranging from 235 sf (22 m2) up to 1,670 sf (155 m2). This underground complex includes platform, concourse, cross-passage and emergency ventilation tunnels together with station egress and ventilation shafts. Various excavation sequences are in use for the different tunnels including the twin-sidewall drifts for the impressive45 ft (13.7 m) wide by 42 ft ( 12.8 m) high concourse cross adits. This station has two train platforms approximately 165 feet (50m) below the surface. This station, constructed in highly variable glacial deposits including water bearing sands and silts approximately 50 ft below multiple perched water tables in an urban setting, creates a very unique and challenging situation. The ground is being managed with various types of ground improvements such as jet grouting and vacuum assisted deep dewatering wells from the surface, and from underground by use of “SEM Tool-box Items” such as barrel vault canopy, grouted pipe and rebar spiling, chemical grout,

Jan 1, 2007

By T. P. Dolley

Domestic production of industrial sand and gravel in 2004 was about 29 Mt (32 million st), a 6-percent increase from 2003. This increase was buoyed by a robust construction sector of the U.S. economy. U.S. apparent consumption was 30.3 Mt (33.3 million st) in 2004, an in-crease from 2003. Imports were about 490 kt (540,000 st) in 2004, an 11-percent increase from 2003. Imports of silica are generally of two types. They include small-quantity shipments of very-high-purity silica or a few large shipments of lower grade silica that were shipped only under special circumstances (such as very low freight rates).

Jan 1, 2005

By Raja V. Ramani

As the new millennium approaches, it is appropriate to assess the progress that has been made in mine health and safety, a matter of concern to management, labor and government. One can hardly look at the major events of the last century — from the birth of the US Bureau of Mines through the enactment of the modern health and safety laws — without realizing that the march has been relentless toward eradication of health and safety threats in mining. The progress is spectacular in mine safety and significant in mine health. In looking at the future, it is safe to assume that societal demands will increase for improved health and safety conditions in the workplace. So will the demands for greater technological leaps. The standards will for measuring success and the expectations of progress in creating a safer and healthier mine environment will grow. The possibilities are enormous of meeting these exacting requirements in the 21st century.

Jan 1, 1999

By P. Somasundaran, D. R. Nagaraj, Tarun Bhambani, P. Patra

Flotation separation and recovery of value minerals from ores containing fibrous silicate minerals are known to be quite challenging. Earlier studies have established that the metallurgical challenges (poor selectivity and recovery, high energy consumption, etc.) arise from the impact of the fibrous minerals (with high aspect ratio) on pulp rheology, which was found be rather complex. The complex rheological behavior of ore suspensions containing particles with high aspect ratio and its influence on flotation outcome are investigated in this study. Flotation tests and rheological measurements were carried out with both ores (containing fibrous minerals) and a model system comprising nylon fibers (chemically inert) added to a copper ore that had no fibrous mineral. These studies allowed the determination of contributions of physical properties of the fiber to pulp rheological behavior. Optical microscopy images of the fiber pulp indicated that the fibers entangled to form two levels of microstructures: two-dimensional (2D) aggregates under semi-dilute (< 20% solids) conditions and three-dimensional (3D) microstructures at concentrations > 30% solids. The yield stress (σ) values determined for the fiber pulp were logarithmically related to the volume fraction of the 2D/3D structures. The relationships developed here for different ARs showed that the yield stress of a flotation pulp changes with respect to shape, size, and the concentrations of the microstructures. Implications to the effects of such entangle networks on selectivity of flotation separation are discussed.

By Vince Luongo

PROJECT DESCRIPTION The York Durham Sanitary System (YDSS) Interceptor in the Town of Richmond Hill located just north of Toronto, Ontario, Canada will see the construction of a tunnel extending along 19th Avenue for a length of approximately 3.8 Km from Yonge Street, east to Leslie Street and will have a minimum internal diameter of 2.1 m. t to Leslie Street and will have a minimum internal diameter of 2.1 m. The tunnel will connect into four shafts, for which two of the shafts will be constructed using the slurry wall construction method given the high water table and difficult ground conditions encountered at these locations. The two shafts noted as Access Shaft No. 2 and No. 3 were designed and constructed to meet regulatory conditions, which required a sealed shaft construction method. GEOGRAPHICAL PROFILE The ground conditions in the Toronto region consist predominately of glacial till, glaciolacustrine and glaciofluvial sand, silt and clay deposits, and beach sands and gravels. The shallow geological formation found in the project area consists of four types of deposits: Oak Ridge Morain deposits, Halton Till, Glacial lake deposits and Organic soils. The Oak Ridge Morain is the dominant deposit encountered along the tunnel alignment. This formation consists of three deposits: The Upper Till, Middle Sand and the Lower Till. Standard penetration tests (SPT) carried out in these deposits measured N-values ranging from 2 to more than 100 blows/300mm which indicate very loose to very dense soil conditions. The Middle Sand deposit will be the dominant feature within the slurry wall construction at access shafts 2 and 3. Access Shaft 3 The base of the slurry wall will be 20.5 M below the ground surface. Slurry wall excavation will be within peat and organic soils found at the upper 3 M, followed by 5 M of the Upper Till. The remainder of the excavation will be within the Middle Sand. The piezometric head elevation is found at the ground surface. Access Shaft 2 The base of the slurry wall will be 22.5 M below the ground surface. Slurry wall excavation will be entirely within the Middle Sand 2.The piezometric head elevation is found at 7 M below the ground surface.

Jan 1, 2007