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ALAN W. CZARNOWSKY RMCMI PRESIDENT 1988-1989 on behalf of the RMCMI Board of Directors and Officers of The Rocky Mountain Coal Mining Institute cordially invites you and your family to attend the 85th Regular Meeting and Convention to be held June 25, 26 and 27, 1989 at Tamarron Durango, Colorado

Jan 1, 1988

By T. H. Chan

As the University of Hong Kong and their advisors planned their new Centennial Campus it became clear that they would have to re-provide existing water reservoirs on an adjacent site with new salt water reservoirs located underground in two new caverns. The existing reservoirs are owned by the Water Supplies Department who provide salt water for sanitary flushing and a separate potable water supply for regular use. Although underground reservoirs had not previously been adopted locally, the planning has been completed to a tight schedule and the construction is well advanced. The need to preserve historic buildings imposed constraints, as did the requirement to minimise potential construction nuisance for the local community and environment. This paper presents the background to the project and the work carried out to develop an innovative, sustainable and environmental acceptable solution. Construction progress to date is also presented.

By Kewal K. Kohli, Richard E. Thill, Syd S. Peng

The results of unpublished investigations into surface subsidence from coal mining in the Northern Appalachian Coalfield are summarized. These investigations were carried out by various coal companies and the State of Pennsylvania in the sixties and seventies. Subsidence data were collected and analyzed from 10 room-and-pillar panels in 5 mines in the Pittsburgh coal seam. Results show that angle of draw ranges from 26° to 33° and subsidence factor from 0.42 to 0.72; surface heating generally occurs beyond the edges of the panel, the amount and extent of which vary; waviness occurs in the subsidence profile if a substantial number of pillar stumps are left in irregular patterns; interpanel effect is significant; time-dependent subsidence exists, but varies for different panels; and surface slope does not seem to affect the amount of subsidence.

Jan 1, 1982

By Romano J. Micciche

One of the largest scale uses of a multiple, high-strength steel bar tiedown system is described. Tiedowns were installed to resist hydrostatic uplift forces acting on a section of the Interstate Highway Route I-90 southern approach roadway to the Third Harbor Tunnel, in Boston, Massachusetts. Site specific information is discussed regarding design, testing, and installation of Tiedowns. Conclusions are presented regarding the overall performance of this system and the application of this type of tiedown system on future projects.

Jan 1, 1994

By Dean McDonald

The Committee Bay Greenstone Belt extends over 300km and is one of the largest unexplored greenstone belts in North America with excellent gold and diamond potential. Committee Bay Resources Limited holds over 550,000 acres of land with prospective geology in the Committee Bay area southwest of Melville Peninsula, Nunavut. Committee Bay is a typical Archean greenstone belt comparable to the Yellowknife, Red Lake, Kirkland Lake and other prolific gold belts. Drilling during 2003 at Committee Bay resulted in: 1) the discovery of high-grade gold-bearing quartz veins with silicification and sulphidation at Three Bluffs, and 2) the continuation of high-grade gold mineralization in the hinge area of the iron formation at Inuk. Gold mineralization at Three Bluffs is identified in iron formation and adjacent sediments and has been traced by drilling for over 700m. The Three Bluffs iron formation is open to depth and along strike where is has been traced on surface for over 6km. In January 2004 Committee Bay and joint venture partner Gold Field?s announced a $7.1 million exploration program for the Committee Bay project in 2004. A total of 8,000m in exploration drilling has been approved for the expansion of the Three Bluffs to the resource stage and drilling of at least five new target areas. Additional mapping, sampling and geophysics will be used to identify new gold targets along the very prospective Committee Bay belt.

May 1, 2004

By A. J. Thompson

The Metropolitan Transportation Authority (MTA) East Side Access project (ESA) will, when it is complete, provide a new link to the east side of Manhattan from Long Island, NY that, linked with the Second Ave. Subway currently under construction, will assist in relieving overcrowding at Penn Station as well as the Lexington Ave. subway. ESA will bring Long Island Railroad (LIRR) directly from Long Island into a new station located 37 m (120 ft) beneath the existing Grand Central Terminal (GCT) located in the heart of Manhattan. It will connect the LIRR?s mainline tracks in Queens, via the existing 63rd Street Tunnel under the East River, to a new terminal constructed within, and beneath, the historic Grand Central Terminal.

Jan 1, 2012

By K. Galovich, P. Krivokuca

"Quinsam coal mine is located about 25 km west of Campbell River on the east coast of Vancouver Island, British Columbia. Using continuous miners in a fully mechanized retreat room-and-pillar operation, it produces low sulphur, “super compliance” thermal coal for domestic and international markets at a rate of about 2600 t/d. Currently, 65 people work at the site, including some corporate employees.Opened in 1993, the Quinsam mine had a dismal safety record until 1997. Lost time injuries and medical aids were unacceptably high. In 1998, a change in corporate structure brought a change in safety attitudes; a total and unequivocal commitment to safety as job No.1 by corporate and site management. This commitment was clearly spelled out in a new mission statement, circulated to all employees by the new President and CEO, David Slater: “Safety is job No. 1; Production flows from safety; and Think safety at all times.” As well as re-defining workplace safety practices, QCC tightened engineering controls and enforced strict adherence to mine plans.This paper provides a general background to the mining operation, and describes the safety practices that have resulted in an enviable safety record in recent years, reflected by provincial and national recognition."

Jan 1, 2004

By Nick Barton

When the Q-system was launched in 1974, the name referred to rock mass classification, with focus on tunnel and cavern support selection. Besides empirical design of support, the Q-value, or its normalized value Qc, has been found to correlate with seismic P-wave velocity, with deformation modulus, and with deformation. The Q-system provides temporary or permanent support for road, rail, and mine roadway tunnels and for caverns for various uses. It also gives relative cost and time for tunnel construction for a complete range of rock qualities. There are also indications that Q has captured important elements of the cohesive and frictional strength of rock masses, with Qc resembling the product of rock mass cohesion and rock mass friction coefficient.

Jan 5, 2007

By Svend [Bue] Rondum

The final report contains a summary of the work performed under this contract, In addition to the report itself, other products were derived from this effort. Several hardware items were prototyped for use with underground belt conveyors, and a manual for installation and maintenance procedures was developed and published under separate cover. Recommendations have been included for implementation of the tools and the manual or, an industry-wide basis.

Jan 1, 1982

By Joseph Daniels

[Adequate supplies of suitable coal and coke are prime requisites in many industries, particularly those dealing with the utilization of mineral resources, recently interest has been focused on the possibilities of using electricity produced at Bonneville and Grand Coulee, Wash., in many electrochemical and electrometallurgical processes, in which core or some form of carbon is necessary in addition, discussion has been revived on the possibility of making iron and steel by the conventional methods employed in blast and open-hearth furnaces. The subject also is important at this time because of its relationship to industrial preparedness for national defense. A supply of coke from local sources on the Pacific coast is necessary in any program of production for strategic sufficiency of certain materials. An anal trio involving tae establishment of such industries should include detailed data on available supplies of coal, the quality and properties of the coke produced, and the technologic and economic factors involved in manufacture of echo and disposal of byproducts.]

Jan 1, 1941

By Dan A. Brown

Outline ? Basic Concept of ACIP Piles ? Factors Affecting ACIP Pile Performance ? Applications: - Favorable Conditions - Unfavorable Conditions ? Design for Axial Loading ? Lateral Loading Considerations ? Summary & Conclusions

Jan 1, 2004

By R Munoz, R González, J Vallejos, A Delonca

In panel caving in underground mines, it is essential to characterise and monitor the stress and stability state of production level pillars to ensure the extraction of the mineralised ore column and the safety of workers. Pilar Norte is a sector in the El Teniente mine that forms a pillar between the undercut fronts of the adjacent Esmeralda and Reservas Norte sectors. It exists in a high-stress environment, which may induce damage to the rock mass production pillars. Generally, numerical models are calibrated using observed damage in galleries. This procedure does not discriminate between the structural condition and/or the blasting damage effects. This paper proposes a technique that uses borehole cameras to measure stress-induced damage. This has the advantage of being at the intact rock scale, meaning that the effect of geological structures is negligible and the blasting damage factor is eliminated. Comprehensive geotechnical characterisation and tomography monitoring has been undertaken at Pilar Norte to describe and determine the rock mass behaviour of the production pillars. By combining analytical, empirical and numerical models, a correlation between the measured overbreak recorded by the borehole cameras and the stress level of the pillar was developed. The methodology can be routinely applied to estimate the stress state in the production pillars.CITATION:González, R, Munoz, R, Vallejos, J and Delonca, A, 2016. Characterisation and monitoring of the stress state of production pillars at El Teniente Mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 197–202 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By Pamplinm J. W.

"INTRODUCTION For the past six years the United States Bureau of Mines in cooperation with the University of Alabama, Tuscaloosa, Ala., the Missouri School of Mines and Metallurgy, Rolla, Mo., and certain operating companies of the Florida land-pebble phosphate district have conducted an investigation to determine the amenability of phosphatic sands to concentration. 4 This paper discusses briefly an investigation of the concentration of fine phosphatic sanads of the land-pebble district of Florida. The process used - namely, the tabling of material previously given a selective oiling treatment - is new in its application to the phosphate industry, although old in principle.The feed to the standard phospidate washery is a hydraulically wined mixture of phosphate pebbles, quartz sand, and clay in which the quartz sand grains are segregated in the fine sizes. Me standard method of concentrating (washing) consists of wet-screening. at about 20 mesh to recover the plus 20-mesh material. 5 Lately some of the washeries have introduced hydraulic classifiers for sizing of the screen undersize to recover the coarser spigot products, but even this additional treatment allows much of the fine phosphate to be wasted."

Dec 1, 1932

By John P. Davis

The use of conventional, circulatory air rotary and fluid rotary, cased and uncased drilling methods in the vicinity of sensitive infrastructure can have deleterious effects on the ground conditions surrounding and supporting structures and the structure itself. Furthermore, the use of these conventional methods offers the engineer or contractor little information about the condition of the subsurface during geotechnical applications. Conversely, sonic drilling measurements and samples can be used to evaluate actual conditions during the progress of exploration and construction across a given site. This paper will discuss the history and properties of sonic drilling and explore case histories of geotechnical applications for the advancement of boreholes within vulnerable structures and on sensitive sites for several recent infrastructure projects ? a tunnel and railroad project, a dam grout curtain project, a bridge micropile exploration project and a tunnel instrumentation project. Project summaries will discuss the advantages realized when the application of sonic drilling techniques demonstrated superior accuracy, quality control, efficiency, productivity, penetrability, waste minimization and adaptability when drilling adjacent to or within existing infrastructure. Finally, the discussion will address the current testing and application of sonic drilling to the installation of micropiles, earth retention anchors, grout injection and instrumentation installation where the quality control benefits provided by the inherent soil cores, measurement while drilling systems, accuracy and non-destructive production drilling features will be advantageous.

Jan 1, 2006

By John Sleavin

As part of the Link Light Rail project in Seattle, WA, work was completed at the Pine Street Stub Tunnel (PSST) in early 2007 for the Central Link project. This tunnel was excavated using cut-and-cover construction within the limits of Pine Street. The stub tunnel provides a turn back via double crossover for light rail trains running in the Downtown Transit Tunnel (DTT), as well as a connection point for the next phase of the project, the University Link (Fig. 1). Designing the new University Link tunnel connection to the existing PSST was a tricky task. The on-site geotechnical conditions, buried obstructions, geometry, requirements for construction and balancing operational considerations and neighborhood stakeholder concerns associated with the recently completed PSST combined to create a uniquely challenging assignment.

Jan 1, 2010

By J. Chlopas, D. J. Barratt, M. V. Sharp

"This paper describes the modifications made to the Fox Mine copper concentrate bin in order to obtain a continuous flow condition. The design of these modifications is based on test results obtained on Fox Mine concentrate using the flow factor testing machine in the research facilities of Cominco at Trail, B.C.The original design consisted of a cylindrical steel bin on a concrete slab with two slot-discharge openings. Based on predictions of the maximum mass flow hopper angle for conical and wedge shaped hoppers for the concentrate on various potential bin lining materials, Ultra-High Molecular Weight (UHMW) Polymer was selected as a liner.Using the recommended angles for conical and wedge shaped hoppers, the profile of the bin base was changed to suit the existing slot openings.The initial method of fastening the liner resulted in failure of the connections. Subsequent modification to the zinc concentrate bin fastener system proved satisfactory and it has now been in operation for over one year without any separation of the lining material.Utilization of flow testing procedures on concentrate samples has demonstrated that proper design of storage bins or hoppers to achieve continuous flow can be incorporated into the design of new plants."

Jan 1, 1978

A preliminary program dated April 25, 1974, was prepared for Development Engineering, Inc. (DEI) on research and development. for laboratory, field and other engineering studies on the disposal of retorted oil shale. This program was revised and published as a final document dated December 17, 1974. The document included discussions on the peculiarities of retorted shale materials to be investigated and discussions of the various laboratory and field tests which would need to be conducted to define their physical and chemical properties. The proposed research and development program was divided into eight work phases as follows: I Program Development. II Exploratory Laboratory Tests on Old U.S.B.M. Retorted Shale. III Laboratory Tests on Pilot Plant Retorted Shales, IV Laboratory Tests on Retorted Shale from the Semi-Works Plant, Field, Test Plots and Ponds. V Field Compaction Tests. VI Infiltration Pond Tests. VIII Final Report.

Jan 1, 1975

By R. S. Dean

In addition to the normal work and that pertaining to strategic minerals, the Metallurgical Division has been made responsible for carrying on major investigations in the development of processes' for the treatment of low-grade domestic manganese ores that heretofore have failed to yield products suitable for the preparation of ferromanganese, an alloy essential to every ton of steel produced. These investigations are particularly important at this time because of their part in tucking this country self-sufficient with regard to manganese when the stock-piled ore becomes e exhausted and as foreign shipments of ferro-grade ore are cut off. The results indicate that there is a good probability of accomplishing this objective, while at the same time conservation may be promoted through the use of normally useless material from the large, low-grade ore deposits.

Jan 1, 1941

By Lottrey A. L, Sowerby B. D, Cutmore N. G

On-line monitoring of low rank coal quality during input to a process has the potential to provide benefits through: ò anticipation of coal quality variations prior to utilisation; ò provision of a tool to help determine the influence of coal quality on process behaviour, and ò provide a direct measure of coal quality for pricing. Moisture and ash are the two most significant coal quality parameters for combustion. They determine the energy content which can be derived from the coal and the problems arising from the presence of ash in the process (eg ash fouling, corrosion, erosion, particulate emissions and ash disposal). Extensive pilot-scale testing and full-scale experience has shown that specific coal/ash constituents (eg Na2O/ash ratio, acid-soluble aluminium, silica, sulphur contents, etc) are also important for the behaviour of Latrobe Valley brown coal during combustion, ash formation, deposition and removal of ash in precipitators and furnace ash hoppers. This paper discusses the range of on-line analysis techniques which have been investigated and their application to low rank coal analysis. Preliminary results from a joint SECV/CSIRO project which aims to develop two separate advanced instrument systems are also presented. These systems are based on: ò microwave attenuation and phase shift - for direct determination of moisture content; and ò inelastic neutron scattering - to provide total hydrogen, carbon, chlorine and ash contents, with potential for calculation of moisture content, specific energy, sodium content and Na20/ash ratio using correlations.

Jan 1, 1992

By J. D. Steenkamp

Southern Africa has a history rich in the pyrometallurgical processing of ores. Two of the alloys produced are high-carbon ferromanganese (74?83 per cent Mn) and silicomanganese (59?67 per cent Mn and 14?31 per cent Si). The largest land-based manganese ore deposit in the world is based in the Northern Cape Province of South Africa. In 2010, 6.3 Mt of ore from the deposit was exported, mainly to China, Norway, Japan, and India, and an estimated 1.1 Mt beneficiated locally to produce manganese ferroalloys. In southern Africa the producers of manganese ferroalloys are Metalloys and Assmang, and of silicomanganese Transalloys, Mogale Alloys, and Match Corporation. Submerged arc furnace technology is utilized in the production of high-carbon ferromanganese (HCFeMn) and silicomanganese, applying the discard slag practice in both instances. The carbon content of HCFeMn is reduced using converter technology and that of SiMn using the Perrin process. Ninety per cent of the world?s manganese ferroalloys production is consumed by the steel industry. The consumption (and production) of manganese ferroalloys therefore closely follows worldwide steel production. From 2001 to 2010, the doubling of the worldwide production of manganese ferroalloys can be attributed to an increase in production capacity in Asia and Oceania, with the largest increase in the production of SiMn. Manganese ferroalloys produced in Asia and Oceania are mainly for the local market, with North America, Europe, Russia, and Turkey the major markets for alloys from southern Africa. The major challenges faced by the southern African manganese ferroalloy producers are increasing electricity tariffs and productivity of labour, which require a concerted effort by all parties involved to achieve a satisfactory solution. Keywords manganese ferroalloys, ferromanganese, silicomanganese, southern Africa, South Africa, manganese ore, high-carbon ferromanganese, refined ferromanganese, refined silicomanganese.

Aug 1, 2013