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By Victor J. Scaravilli

This report is based on experience developed on the construction of one contract for the Buffalo, New York subway. The Buffalo subway is under construction for the Niagara Frontier Transportation Authority and is called the LRRT-Light Rail Rapid Transit or more commonly the Metro. The Initial Route of the Buffalo subway construction started early in 1979 and is scheduled for completion in May, 1984. The initial system includes 5.2 miles of underground construction, 1.3 miles at grade for a total of 6.5 miles of subway system. A total of fourteen stations, eight underground and six at grade are included on the system. The Initial Route has a planned expansion to 17.3 miles in the future. On January 15, 1979, a Joint Venture of S & M Constructors, Inc., Solon, Ohio, James McHugh Construction Co., Chicago, Illinois, and Kenny Construction Company, Wheeling, Illinois, was awarded contract 100031, the Line Tunnels from Amherst Street to South Campus in northcentral Buffalo between Delaware Park and the State University, (see Fig. 1, Location Plan) This $35,000,000.00 contract was designed by Hatch Associates Consultants, Inc., Buffalo, N.Y. The Notice to Proceed was issued January 15, 1979 and the scheduled completion date is August 18, 1981. The project consists of two parallel rock tunnels with a minimum excavated diam of 18 ft 0 in. and a final concrete lining of 16 ft 0 in. diam. The tunnels total 14,630 linear ft. In addition to the tunnels, contract C-31 includes four shafts, an underground pump station, three cross passage connections, and other minor work items. (see Fig. 2, C-31 Project Plan and Profile) The tunnels were constructed primarily within the Bertie Formation, an approximately 50 foot thick moderately fractured to massive, dolo-

Jan 1, 1981

By Harry R. Asche, Manfred K. Lechner

The Cross City Tunnel comprises 2km of a new underground traffic route in Sydney, Australia. The route is very complex, involving some six separate tunnels and three underground Y-junctions. For almost 200m the six tunnels run parallel at different level sunder William Street, Sydney. Almost all of the route runs adjacent to the City Business District of Sydney and adjacent to or below many major buildings and services. The planning and design of this project is described. The geometric arrangement is achieved with a strong dependence on 3D road design packages. Road alignment constraints include land acquisition and proximity to existing tunnels and basements as well as maintaining separation from the other tunnels in the scheme. Geotechnical and hydrogeological studies are described. Findings discussed include the high horizontal stress field in the Sydney area and investigation of incised palaeochannels on the route. Methods of design for the tunnels and Y-junctions are described, as well as methods of settlement prediction for the buildings and services. The latter includes the settlement assessment for more than 200 buildings, many in excess of 20 storeys, as well as services including all of the city railway lines in Sydney.

Jan 1, 2003

By R. H. Moore, B. D. Breitenstein

INTRODUCTION The United States Uranium Registry (USUR) tissue program was funded in 1978 by the United States Department of Energy (DOE) through its Human Health and Assessments Division, and registrant enrollment began in 1980. It is operated by Hanford Environmental Health Foundation (HERF), Richland, Washington, with support provided by Pacific Northwest Laboratory (PNL).** The USUR tissue program is the first systematic effort to contact and gain assistance of workers occupationally exposed to uranium and to seek and study uranium deposition in human tissue. This paper describes the program objectives, populations selected for study, procedures for enrolling workers in the program, types of tissue to be studied, and analytical procedures to be used. PROGRAM OBJECTIVES The objectives of the USUR tissue program are to: 1) Determine the distribution and concentration of uranium, if any, in the tissues of occupationally exposed workers. 2) Compare bioassay measurements of exposed individuals with the results of analyses of tissues obtained at autopsy. 3) Seek evidence of histopathologic changes related to any uranium deposition that may be present. 4) Conduct analyses of whole bodies, when available, to obtain more precise data on the uranium burdens, if any, in the body and organs, and especially the distribution in parts of the body, such as the skeleton, that are not usually accessible for sampling. 5) Develop data that will assist in evaluating a) the accuracy of current in-vivo measurement techniques, b) the propriety of existing regulations, and c) the adequacy of current protection programs. SELECTION OF POPULATIONS FOR STUDY Selection of the populations for the USUR tissue program was based on studies of the United States Uranium Registry described elsewhere (0c81). Potential populations for study were quite varied because of occupational exposure to different chemical forms of uranium, different levels and eras of exposure, varying ability to identify populations exposed in the past, and the general interest and cooperativeness of the populations. Nevertheless, certain identifiable populations emerged that were both willing to participate in the study and likely to provide useful information. Among the targeted populations are individuals who were exposed to uranium prior to the existence of modern exposure standards. These individuals are presently being enrolled by the USUR. The reliability of concentration and distribution data and the demonstration of effects are more likely in such individuals than in those who have received less exposure. However, the targeted groups also include individuals who Have been exposed to permissible levels of uranium, and reference employees in uranium plants who have not worked with uranium. The lesser exposures are of immediate interest because of the rarity of heavy exposures under current standards. The sampling of potentially exposed individuals with negative in-vivo measurement results may serve to check the adequacy of in-vivo measurements in the detection of deposition. [ENROLLMENT PROCEDURE] The enrollment of participants follows three patterns. 1) Presently employed workers are enrolled by the cooperative efforts of USUR staff with the medical, industrial relations, and/or health physics personnel of the uranium facility. Volunteers may be enrolled by medical personnel at the time of their physical examination or by health physics personnel at the time of a bioassay or lung counting procedure. Follow-up after initial contacts with currently employed uranium workers is carried out by on-site personnel, but subsequent follow-up is the responsibility of the Registry. 2) Retired workers are contacted by mail, with a covering letter from their former employer supporting the principles of the study but leaving participation in the program on an entirely voluntary basis. 3) An alternate method of enrollment is to obtain a USUR autopsy consent after death from the next of kin. As part of enrollment in the program, permission is requested for access to the individual's medical and exposure data, and a short occupational history is filled out. The autopsy permission agreement signed by the individual is for an initial period of 5 years; the USUR ordinarily seeks renewal of the agreement upon its expiration. While this agreement provides

Jan 1, 1981

By G. Schubert, H. Hoberg

A large number of diverse size reduction machines is currently available for the comminution of waste materials. Equipment selection is determined by the nature of the material to be treated and by its behavior under external mechanical stressing. Accordingly, wastes can be divided into those with elastictbrittle and those with ductile/viscous behavior. The scientific understanding of the comminution of wastes is lagging strongly as compared to that of the grain-shaped mineral raw materials. Only in a few unique cases have the fundamentals of the comminution of ductile or viscous materials been presented. The paper centers on a characterization and systematic analysis of the types of stress fundamental to comminution. On the basis of this discussion an overview is presented of the currently available technologies for the comminution of wastes, with attention centering on those machines designed for materials with ductile or viscous behavior.

Jan 1, 1998

By Michael Jatczak, Brett Robinson

The South Bay Ocean Outfall tunnel is located at the U.S./Mexico Border and is one link in a system designed to treat and dispose of raw sewage entering the Tijuana River Valley from Mexico. The 11 finished diameter tunnel extends 19,000’west from the bottom of a 200 deep, 36 diameter drop shaft. At the western terminus of the tunnel, a Riser shaft connects the tunnel to conveyance and diffuser pipes on the seabed. The tunnel runs through the San Diego Formation, consisting of clay, silt, sand, gravels, cobbles, and boulders. A Mitsubishi Earth Pressure Balance (EPB) Tunnel Boring Machine equipped with a large variety of monitoring and control devices was used. This paper will provide an overview of the Project’s construction, with special emphasis on the value of the electronic data acquisition system.

Jan 1, 1999

By T. S. Golosinski

This article reviews current contract mining practices in Australia. Various types of contracts are reviewed, including partnering arrangements and alliances between the contractor and the mine owner. Applicability is also discussed of various types of contracts to specific mining situations, as is their effect on overall mine performance.

Jan 1, 1998

By James P. Morris, William H. Hansmire

The U. S. Department of Energy's (DOE) Yucca Mountain Project (YMP) is a scientific endeavor to determine the suitability of Yucca Mountain for the first long term, high level nuclear waste repository in the United States. The status of this long-term project from the construction perspective is described. A key element is construction of the Exploratory Studies Facility (ESF), which is being excavated with a 7.6 m (25 ft) diameter tunnel boring machine (TBM). Development of the ESF may include the excavation of over 15 km (9.3 mi) of tunnel varying in size from 3 to 7.6 m (10 to 25 ft). Prior to construction, extensive constructibility reviews were an interactive part of the final design. The intent was to establish a constructible design that met the long-term stability requirements for radiological safety of a future repository while maintaining flexibility for the scientific investigations and acceptable tunneling productivity.

Jan 1, 1995

By Gregg R. Bierei

Arch of Illinois is a mining complex comprised of two surface and two underground mines located in Perry County, in southern Illinois. The company a division of Apogee Coal Co. of St. Louis, MO. Arch of Illinois' two surface mines, the Captain and Horse Creek Mines, use large stripping shovels and cross-pit bucketwheel excavators to remove overburden from three seams of coal, the Herrin No. 6, Harrisburg No. 5 and Danville No. 7. All are considered high sulfur reserves. The two underground operations are managed by Arch of Illinois. They are the Kathleen Mine and the newly constructed Conant Mine, which began production in 1991. Both underground mines are continuous miner operations. They mine the No. 6 coal, which is about 1.8 m to 2.1 m (6 to 7 ft) thick. All coal is currently transported by truck to a central preparation plant located at the Captain Mine. This preparation plant produces 27 kt/d (30,000 stpd) of clean coal. Production in 1992 reached 5.9 Mt (6.5 million st) of saleable coal. Of that, about 66% or 4 Mt (4.4 million st) are produced by the surface mines and the rest the by under ground operations. Change is in the wind for Arch of Illinois. In 1988, 100% of all production (6.2 Mt or 6.9 million st) came from surface operations. By 1995, only 38% of production is scheduled from surface mines. And by the year 2000, 100% of production will from underground mining methods. Dwindling low ratio reserves, compounded by increasing environmental and land acquisition costs, coupled with more efficient underground mining equipment, have started an evolutionary trend toward development of underground reserves. For Arch of Illinois to maintain profitability of remaining surface reserves and to compete effectively mining underground, it must improve efficiency, productivity and cost reductions. These efforts are essential for maximizing current surface reserves and to ensure a continued existence in the presence of clean air legislation and the softening of the high sulfur coal market.

Jan 1, 1993

By John A. Herbst

At the last Comminution Symposium a challenge (Meloy and Williams, 1992) was issued to "predict the typical straight-line, self similar" tumbling mill product size distributions using a population balance model (PBM). Implicit in this challenge is the assumption that the PBM is inadequate for predicting real world grinding performance. This response is presented in three parts: I. Theoretical analysis of the general PBM and its appropriateness for comminution system modeling. II. Examination of the accuracy of prediction of real world milling behavior using linear and nonlinear PBMs. III. Evidence from recent microscale comminution research. This paper concludes with recommendations concerning future research which will: 1. further elucidate mechanisms of particle destruction and creation as well as attrition and 2. increase the accuracy of model predictions in highly nonlinear situations

Jan 1, 1997

By John E. Frost

The Gibralter Mines Ltd. complex is 61 km (38 miles) north of Williams Lake in central British Columbia, Fig. 1. The discovery of these deposits evolved in stages such that each stage revealed a bigger piece of the elephant. When the elephant was mostly revealed, Placer Development Ltd. brought the property into production. Although Gibralter is aporphyry copper deposit, it is certainly not a typical one. Copper and minor molybdenum mineralization occur in a foliated and saussuritized quartz diorite. Ore bodies tend to be tabular in form because foliation exerts a major control on localizing mineralization. A generalized geologic map of the Gibralter-Pollyanna area is shown in Fig. 2. Mineralization was first identified in 1917 in the Pollyanna area. Several shallow pits were sunk on flashy, but low grade, lenticular quartz veins. Duval Corp. made the initial commercial discovery, the Pollyanna ore body, on what were then called the Pollyanna claims. These claims, staked by R.C. Glen and C. Gennis in 1963, were the first to be optioned by Duval in British Columbia in October 1964. Placer Development joined Duval in late 1966 as a 50% joint venture partner, and after optioning the adjoining Gibralter claims, proceeded to evaluate and develop the four ore bodies that make up the Gibralter deposit. The Gibralter claims south of the Pollyanna claims provided the name for the Gibralter deposit.

Jan 1, 1991

By John D. Shaw

1. Introduction 2. The Hydraulic Mine _ (i ) Development (i i ) Extraction ( i i i ) Transport 3. The Water Circuit 4. Manpower and Results 5. Modifications 6. Conclusions 1. Introduction The Kaiser Resources Ltd. hydraulic coal mine is located in south eastern British Columbia, Canada, at the western end of the Crowsnest Pass, next to the Town of Sparwood. The seam presently being mined is the number 10, known locally as the Balmer seam, which is a high quality coking coal, 50 feet in thickness and of an average inclination of 35 degrees. The mine was designed in the late sixties as a small scale trial unit, and was to use a single monitor unit, working 3 shifts per day on a 5 day per week basis. Experience has proved the method to be so successful as to warrant the expansion of the ancilliary facilities to cater for the increased production. The annual raw coal production from this single monitor unit has risen from 108,988 short tons in 1970 to 942,334 short tons in 1975, with a total mine labour force of about 160 men including the surface de-watering plant, mine supervision and mine administration.

Jan 1, 1977

By Ronald K. Frobel, Christopher J. Wienecke

Geomembrane systems and associated geosynthetics such as geotextiles, geonets, geogrids and geocomposites have been used in precious metal heap leach and tailings facilities for many years. Geomembranes have been used in the heap leach process in pad design and solution recovery ponds as well as associated collection channels as the primary liquid barrier to contain and collect metal bearing leach solution. Geomembrane systems offer an effective, low cost alternative to other containment methods such as compacted low permeability soils, asphalt or concrete. In the 19BO's, rigid High Density Polyethylene (HOPE) liners were used to a great extent with a gradual transition to the use of the more flexible Very Low Density Polyethylene (VLDPE) and Polyvinyl Chloride (PVC). These three geomembrane systems have been used successfully in precious metal heap leach solution containment. Predominant material thicknesses have been 30 and 40 mil for PVC, 40 and 60 mil for HOPE and VLDPE. Variants in recent years have included roughened HDPE and VLDPE to provide higher surface friction characteristics, as well as newer polymer materials such as polypropylene. In addition to providing an economical method for providing enhanced solution recovery, geomernbranes are also providing the primary liquid barrier for prevention of groundwater contamination. Because heap leach solution chemical components and dissolved metal constituents are classified as toxic substances, they are subject to environmental regulation. Many regulatory agencies are still developing guidelines for heap leach pad design, however a geomernbrane liner system is often used as a single liner or in conjunction with other materials to form composite double or even triple lined systems. "Other" materials can include alternate layers of drainage aggregate, geotextiles, clay layers and other geomembrane or geocomposite layers.

Jan 1, 1993

By J. E. Brownhill

After being closed for three years, Specialty Minerals Inc.'s Port Inland limestone facility reopened in the spring of 1992 as a commercial limestone producer. In 1990, Specialty Minerals, a division of Pfizer Inc., bought Port Inland's reserves and equipment from Inland Steel because of the strategic value of the limestone for the production of precipitated calcium carbonate (PCC). Specialty Minerals' project team faced many challenges in reconstructing the Port Inland facility. Many traditions and norms had to be overturned to achieve the productivity, flexibility and cost necessary to survive in today's competitive minerals environment. Port Inland's history Inland Steel built Port Inland in 1930. It was operated as a captive source of metallurgical grade limestone for the steel industry until its closure in 1989. The facility is located in the Upper Pen¬insula of Michigan on the north edge of Lake Michigan. Operations consist of a deep water port facility with crushing, screening and stockpile storage for 453 kt (500,000 st) of finished product at the port. Ninety-nine percent of the stone is shipped by lake boat to ports within the Great Lakes. The operation is unique in that both metallurgical dolomite and limestone are produced on site.

Jan 1, 1994

By Margaret Armstrong, Arne Berckmans

The longterm aim of this research project is to find fast ways of simulating the recoverable reserves of a deposit for input into financial Monte Carlo simulations without having to conditionally simulate the whole orebody many times. The first step in this re- search is to visualize and quantify the ore tonnage T and the metal quantity Q above an arbitrary cutoff z. This paper presents detailed results for one specific distribution, the lognormal. These lead to a suggestion of a fast way of simulating QTz curves.

Jan 1, 1996

By M. T. Heath

Numerous mineral deposits of somewhat limited extent and grade are associated with most of the Tertiary granitic intrusions in the Cascade Mountains of Washington. The Silver Star area in southwestern Washington is typical of many of these small, and at the present time, economically marginal mineralized areas. Small but fairly high grade deposits of copper, lead, and zinc sulfides are found within the borders of a small granodiorite stock, and in surrounding Tertiary volcanics. This paper will discuss these deposits and their genetic relationships with the intrusion.

Jan 1, 1967

By Robert M. St. Louis, Janet M. Edgecombe

The Mercur Mine's autoclave is an alkaline pressure oxidation system, operating at 220°(428°F) and 3061 kPa (444 psig) (total). Up to 725 metric tons (800 st) of ore, grading 2.02 g per mt (0.059 oz/st) Au and containing 1 to 2% sulfide sulfur, are treated daily in this circuit. A mineralogical and chemical investigation was initiated to locate the cause of lower than anticipated gold recoveries. Greater than 70 wt. % of reduced sulfur is oxidized; therefore, the autoclave is operating at specification. The low recoveries were attributed to increased concentrations of organic carbon in refractory ore. Activated carbon concentration in the attached CIL circuit was increased from 15 to 40 g per 1, leach temperature held below 21°C (70°F), and carbon flow changed to counterflow. These measures resulted in gold recovery improving from 75 to 82%.

Jan 1, 1990

By D. Altizer, E. Thompson, K. F. Unrug

Because of frequent sudden changes in the geologic composition of strata, the extrapolation of rock properties obtained from core samples to the surrounding areas can cause problems. To address this issue, a method of rapid strength testing in situ using a borehole penetrometer is being developed. This method, as opposed to conventional laboratory testing, does not require rock samples to be retrieved and handled/machined before testing. Rock strengths are determined di¬rectly on the drill-hole wall. The latest development is a borehole penetrometer that requires only a 38.1-mm- (1.5-in.-) diam hole. The small diameter of the penetrometer body allows for the drilling of test holes with production mine equipment such as a roof bolter. The new penetrometer allows for the possibility of a broad application in coal mines, as well as in hard rock mines and tunneling. The principles of the apparatus are described and are illustrated with examples of its applications.

Jan 1, 2002

By John R. Marks

The recent trend in the ventilation of deep under- ground metal mines in the United States is to rely more and more on refrigeration for air cooling. This paper describes the layout and the economics of the refrigeration method used by Hecla Mining Company at the Star Mine. An economic analysis must compare the benefits of an engineering system against the costs. The benefits of refrigeration, for example, are increased production rates, a better safety record, improved employee moral, and generally lower airflow requirements. Air-conditioning costs include capital expenditures for equipment, labor and supply costs for maintenance, and power costs for machine operation. A study of whether or not to install refrigeration becomes academic when a mine reaches the critical ventilation depth1 (the depth at which adiabatic compression alone produces station temperatures equal to the desired stope temperatures). Ventilation planning alternatives for such mines, including the Star Mine, are limited to the different methods of refrigeration usage. In this case study of the Star Mine, the refrigeration layout is described in detail. After the system performance is discussed, air-conditioning costs are calculated. The paper then concludes with a cost- benefit analysis of the Star Mine refrigeration system.

Jan 1, 1980

By C. T. Twort

As technology and economic conditions allow mines to operate at ever greater depths, increasing demands are placed on the environmental engineer to adjust the capacity of the installed mine . - refrigeration systems. At the same time the engineer must satisfy the changing legislation, which demands that developments are carried out in as an energy efficient and environmentally accept- able manner. Following the trends outlined above, this paper is written to give an overview of the current and potential future refrigeration technology available to the mining industry. The effects that may be produced by the adoption in mining applications of the new generation of 'green' refrigerants are examined both at the design stage and when considering the viability of retrofitting existing systems so that they comply with the Montreal Protocol. An introduction to the concept of Total Energy Warming Impact (TEWI) is provided, with an explanation of its use in optimising system design and performance, and its incorporation as part of an environmental audit strategy. The paper concludes with a discussion of innovative refrigeration techniques and the possible future developments in legislation.

Jan 1, 1997

By M. Dean Kleinkopf, John Callahan, William M. Shepard, R. N. Schnepfe

Despite lower prices and the uncertain future of nuclear power, uranium continued to be the big attraction in 1979 exploration activity. Uranium again dominated exploration programs across the US-not only in primary producing states such as New Mexico and Wyoming, but in potential producing areas from the northern counties of Minnesota to the Grandfather Mountain region of North Carolina. The moratorium on uranium leasing was lifted in Colorado and Montana, and exploration activity intensified accordingly. In Wyoming, what may be the biggest uranium deposit in the state was discovered by Anaconda Copper Co. near Jeffrey City, but in general, there were few major discoveries and activity was concentrated on existing exploration programs. The Department of Energy expects 1979 uranium exploration expenditures to total $339 million, compared to the $314 million spent by industry in 1978. Surface exploration and development drilling in 1979 is estimated at 16.1 Mm, up slightly from 1978 figures. Gold demanded its share of the spotlight in 1979. Soaring prices lured prospectors, investors, operators, and speculators to Alaska, California, Colorado, and Washington in a small-scale gold fever. Exploration for molybdenum remained strong in Alaska, Colorado, and Washington, where mineralization at the Mt. Tolman prospect is now estimated at 816 Mt averaging 0.09% copper and 0.10% molybdenum disulfide. Again this year, one of the major deterrents to exploration was the drive to set aside huge areas of land as wilderness preserves. In Alaska, where Interior Secretary Cecil Andrus has withdrawn millions of acres under the Antiquities Act, BP Alaska decided to close its Anchorage office, reportedly due to the lack of public lands available for mineral exploration. In both geophysical and geochemical activity, the year is best characterized as one of consolidation and development of previous advances in the state of the art, without any fundamental breakthroughs. Many companies were active in the development of instrumentation. Continuing interest in spectral IP resulted in the introduction of two instruments, one by Phoenix Geophysics, the other to be announced shortly by Geotronics Corp. Radiometric and borehole logging equipment received considerable emphasis, reflecting the continued interest in uranium exploration. MINING ENGINEERING'S review of 1979 exploration activity, including state-by-state highlights and a review of geophysical and geochemical activity, begins on the following page.

Jan 5, 1980