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By Bruno Bussière, Guosheng Zhan, Michel Aubertin, Vincent Martin, Robert P. Chapuis

The study evaluates the hydrological behaviour of exposed and covered waste rock dumps. The objectives were to determine the major factors influencing unsaturated flow in waste rock dumps and covers, and to improve the in-situ, laboratory and numerical modeling characterization methods. Using material properties obtained from in-situ and laboratory tests, waste rock dumps of different configurations, with and without covers, were modeled. It was found that a properly designed “Store, divert and release” (SDR) cover allows most of the water to be diverted downslope and discharged outside of the waste rock dumps. The SDR cover seems to work efficiently even in extreme storm events. The numerical modeling results show that the unsaturated hydraulic properties (e.g. air entry value and water entry value) of the materials largely control the infiltration of water into waste rock dumps.

Jan 1, 2005

By Tripathy A. K, Satapathy B. K, Nayak B, Mohanty J. N, Dey D. N

The paper deals with the metallographic tudy of heat treated chromite and chromite-coke composite briquettes. The briquettes, prepared from chromite concentrate of Orissa Mines using molasses-lime, dextrinelime and tamarind seed as binders, were subjected to different temperatures and examined metallographically. The change of phase with temperature was analysed by X-ray diffraction.

Jan 1, 1987

Bio-Oxidation of Arsenic and Stibium Bearing Gold Ores Bio-oxidation of arsenic and stibium bearing gold ores with acidithiobacillus ferrooxidans was studied. The preoxidation results show that the best bio-oxidation technical parameters are the initial pH in the range of 1.8 ~ 2.0, particle sizes under 0.074 mm, temperature in the range of 25¦C ~ 30¦C and rotating speed of the orbital incubator in 100 rpm ~ 160 rpm. The leaching results show that If the ore, of which contain 10.37 per cent arsenic and 36.81 per cent stibium, is not bio-oxidised, gold leaching is only about 41 per cent, after 8 days oxidised, the result is about 76.55 per cent, which improved about 35.62 points. The relationship between gold leaching and arsenic oxidation is direct proportion, furthermore, it needs only partly oxidise and higher gold leaching could be get, for example, gold leaching is over 90 per cent when asenic oxidation is 60 per cent. The results will provide theoretical and technological supports of bio-oxidation arsenopyrite for pretreating refractory gold ores.

Sep 13, 2010

By William R. Yernberg

SME’s Arizona Conference was held at the Doubletree Hotel at Reid Park in Tucson on Dec. 5and 6, 2004. The annual conference is organized by the Arizona Conference Board of Directors, which represents SME sections in Arizona and adjacent areas. The conference provides an opportunity for individuals and corporations associated with mining in the region to get together each year to discuss the status of the industry. The meeting featured a keynote address and more than30 technical papers. Two years ago, the U.S. copper industry was facing on a run for two years now,” and “both precious metal and base metal prices are going up.” The increases in metal prices were attributed to development in China and other Asian countries. “With a population of 1.6 billion, China has recently created 80 million jobs,” said Silver.

Jan 1, 2005

Quantitative seismology is an important tool for investigating mineinduced seismicity and the quantification of the seismic rock mass response. The spatio-temporal interpretation of seismic data within an ever-changing three-dimensional mining environment provides some challenges to the interpretation of the rock mass response. A grid-based approach for the interpretation of spatial variation of the rock mass response provides some benefits compared with approaches based on spatial filters. This paper discusses a grid-based interpretation of seismic data. The basic methods employed in the evaluation of the parameter values through space are discussed and examples of applications to different mine sites given.

Jan 1, 2014

By Gregory T. Ziegler

A complex soil profile and high water table, together with a below-grade active subway tunnel, an above-ground elevated railway line, and the heavily travelled Northern Boulevard all passing above the tunnel alignment, combined to make mining of New York?s Northern Boulevard Crossing what is widely considered to be the most challenging portion of the multi-billion-dollar East Side Access project. The Northern Boulevard Crossing is a vital link in this project which, when completed, will connect the Long Island Railroad to Grand Central Terminal in Manhattan. How the sequential excavation method (SEM) tunneling was successfully accomplished, despite the obstacles, was a textbook exercise in practical innovation coupled with close cooperation between the owner, the construction manager, Hatch Mott MacDonald, the designer, Parsons Brinckerhoff, the contractor, Schiavone-Kiewit, and spe-cialty geotechnical contractor, Moretrench.

Sep 1, 2013

ONE DAY IN the mid-1880s, in a suburb 0f Pittsburgh, Pennsylvania, there dismounted from a train the two foremost leaders of the day in the coal and steel industries-Andrew Carnegie and H. C. Frick. Their attention was drawn to a well-loaded car of coke, which their experienced eyes recognized as a superior product. "I'll bet you that coke is from the H. C. Frick Coke Company," Mr. Frick challenged. "I'll bet it was shipped by my company." In a spirit of fun Mr. Carnegie accepted the wager. Mr. Frick lost the bet: the coke had come from M0rewood, one of three sites being operated under the direction of a young entrepreneur, Erskine Ramsay. If Mr. Frick's confidence was somewhat dented by this occurrence, the responsibility was his own. He himself had opened the way for Erskine Ramsay to become the youngest of mine superintendents; and he had dispersed all dissension regarding his choice with the words : "I'm not interested in his years, I'm interested in his record. He makes more coke in an oven than any other superintendent. And I'll take 'em out 0f the cradle if they can make coke... Suppose he is only twenty years old? ... The d --- kid is a genius, I tell you." Erskine Ramsay was to follow in the tradition of Carnegie and Frick. Not only was he ambitious and a worker his background had prepared him for it. Coal mining was in the Ramsay blood. His father, Robert Ramsay, of whom the son once stated that he had no superior as coal mining and mechanical engineer in this country, once accounted in these words for the phenomenal accomplishments which had attached to the name "It does no harm to belong to a family of mining engineers who are just as good as any in America-if it is myself that says it." Anyone acquainted with Robert Ramsay's character realized that he was not given to overstatement. And the above-mentioned Mr. Carnegie encountered young Ramsay again, a few years later in his career, and wrote of him to young Erskine's father, that he was "going to be a credit `tae us a' " (a quotation from Robert Burns.) Nor have Mr. Ramsay's achievements been identified exclusively with the industrial field in which he early asserted himself. He has been an inventor whose techniques in mining engineering have received international recognition. As an investor of foresight, he has benefitted others immeasurably, as well as himself, being an influential factor in the upbuilding of several communities in his chosen and well-loved adopted home state of Alabama since 1887. He is a philanthropist whose benefactions have run into millions, the chief beneficiaries being educational and charitable institutions. Amidst his accomplishments the lighter side of life has not been neglected and he is known for his hospitality, his

Jan 1, 1953

Plant based on the New Jersey refluxing process was installed at the Cockle Creek Works of Sulphide Corporation Pty. Ltd. to refine portion of the zinc output from the Imperial Smelting furnace.Refining of impure zinc is effected by distillation in two stages in vertical columns comprising a series of superimposed silicon carbide trays designed such that ascending zinc vapours and descending liquid metal are in intimate contact. In the first stage, portion of the zinc and its cadmium content are distilled from impure feed metal, condensed, and while still molten, fed to the second column in which zinc is boiled under controlled refluxing conditions to remove the cadmium content.The resultant zinc has a purity in excess of 99·995 per cent zinc.The availability of refined zinc has made possible the production of a number of zinc alloys for marketing in addition to the basic grades of zinc.

Jan 1, 1970

By James W. Bass

Introduction Atmospheric fluidized bed combustion (AFBC) is an improvement over coal-fired boiler design. It offers several advantages over conventional boilers. AFBC can meet sulfur and nitrogen oxide emission regulations without the need for add-on flue gas treatment equipment. The relatively low combustion temperature inhibits ash melting, thus reducing slagging and fouling that can in turn increase a boiler's fuel flexibility. AFBC process The fluidized bed boiler that operates at atmospheric pressure on the fire side (AFBC) is relatively simple and no different in purpose from those pulverized coal boilers used by utilities today. Fluidized bed boilers can generate steam at the pressure and temperature needed by modern steam turbines. Only the firing system is different. In fluidized bed combustion, the fuel can be almost any coal or waste fuel. It is burned in the presence of a bubbling bed of limestone. Air is forced through the bed at a velocity sufficient to support the weight of the bed particles. When the bed is fully fluidized, it bubbles like a boiling liquid. Although the burning coal makes up less than 1% of the fluidized bed, all the bed particles are heated quickly by the turbulence. The calcium in limestone reacts with sulfur dioxide produced in coal combustion to form calcium sulfate in a dry solid state. In this way, sulfur emissions regulations can be met without installing flue gas desulfurization equipment. Boiler tubes submerged in the bed absorb heat directly from the turbulent solids. The heat converts water in the tubes to steam or superheats the steam. Because of the intimate contact of the boiler tubes with the fluidized bed, heat transfer is highly efficient. Consequently, less boiler tubing surface is needed to generate the same amount of steam as in a comparable pulverized coal boiler. The optimum temperature for sulfur capture is relatively low, about 815°C (1500°F) as opposed to 1370°C (2500°F) for pulverized coal boilers. This results in the formation of lower levels of NON. Because operating temperatures are below those that fuse coal ash, a single design can burn a variety of coals without slagging or fouling problems. TVA's AFBC development program Tennessee Valley Authority's (TVA) involvement in AFBC development began in 1974 and has addressed the technical uncertainties through a comprehensive program of design, experimental, and analytical studies. In 1979, TVA and the Electric Power Research Institute (EPRI) developed plans for a 20-MW AFBC pilot plant, a 10-fold scale-up over the next largest test facility. Pilot plant design features TVA constructed the pilot plant at the Shawnee Steam Plant near

Jan 4, 1986

By D. W. McDonald, L. M. Heaman, R. A. Creaser, T. Davies, T. Chacko, A. Simonetti

"The Three Bluffs gold deposit is located in the Committee Bay greenstone belt, which forms part of the Rae domain of the western Churchill province, Nunavut, Canada. Gold mineralization is hosted by iron formation of the Neoarchean volcanosedimentary Prince Albert Group, and is associated with silicification (quartz veining) and sulfidation of magnetite and other Fe-rich minerals. Conventional U-Pb zircon dating of a conformable dacite unit within the volcanosedimentary host-rock sequence and a crosscutting diorite intrusion confirm a ~2.7 Ga age for deposition of the supracrustal package. U-Pb monazite dates and Pb isotopic analyses of sulfides were obtained by laser ablation-multicollector-inductively coupled plasma-mass spectrometry (LA-MC-ICP-MS). A subset of U-Pb monazite (1813.8 ± 8.7 Ma) and Re-Os arsenopyrite (1822 ± 21 Ma) dates, combined with a Pb-Pb secondary errorchron age for pyrite and arsenopyrite (1829 ± 77 Ma), suggest that gold mineralization associated with sulfidation of the iron formation occurred at ~1815 Ma, prior to high-grade (upper amphibolite facies) tectonometamorphism in the Three Bluffs area (D2TB/(M2TB). An ~1815 Ma age for deposit formation is broadly consistent with evidence from elsewhere in the western Churchill province and to the southwest in Manitoba and Saskatchewan for a late Trans-Hudson (1.9-1.8 Ga) gold mineralizing event. The majority of U-Pb monazite ages form a second population at 1780.6 ± 4.2 Ma, similar to the age of the majority of Re-Os arsenopyrite analyses (1763 ± 11 Ma). These dates are thought to reflect the timing of peak M2TB metamorphism. 40Ar/39Ar dating of amphibole, biotite, and muscovite yielded plateau ages ranging from 1723.8 ± 9.0 Ma to 1710 ± 17 Ma, which are interpreted to record the timing of postpeak metamorphic cooling to below the respective closure temperatures for Ar diffusion in these minerals. Le gîte aurifère de Three Bluffs est situé dans la ceinture de roches vertes de Committee Bay, laquelle appartient au domaine de Rae dans l’ouest de la province de Churchill, au Nunavut, Canada. La minéralisation aurifère est encaissée par des formations de fer d’âge Néoarchéen appartenant aux roches volcanosédimentaire du Groupe de Prince Albert; la minéralisation est associée à de la silicification (veines de quartz) ainsi qu’à la sulfidation de la magnétite et d’autre minéraux riches en Fe.Les résultats de la géochronologie U-Pb conventionnelle sur une unité de dacite concordante au sein de la séquence volcanosédimentaire ainsi que d’une intrusion de diorite qui les recoupe indiquent que ces roches supracrustales ont un âge de ~2.7 Ga. Les âges U-Pb de la monazite ainsi que les analyses des isotopes du plomb des sulfures ont été obtenus par ablation laser (LA-MC-ICP-MS). Certains des âges U-Pb obtenus à partir de la monazite (1813.8 ± 8.7 Ma) et des âges Re-Os retournés par l’arsénopyrite (1822 ± 21 Ma), en association avec l’âge indiqué par une isochrone à données dispersées « errochron » secondaire Pb-Pb pour la pyrite et l’arsénopyrite (1829 ± 77 Ma), suggèrent que la minéralisation aurifère associée à la sulfidation de la formation de fer s’est formée vers ~1815 Ma, avant que l’événement tectonométamorphique (D2TB/(M2TB) de niveau élevé (faciès des amphibolites supérieures) affecte le secteur de Three Bluffs. Un âge de mise en place de ~1815 Ma pour ce gîte est compatible avec les données en provenance de l’ouest de la province de Churchill ainsi que plus au sud-ouest au Manitoba et en Saskatchewan qui indiquent la mise en place de minéralisations aurifères à la fin de l’orogénèse Trans-Hudsonienne (1.9-1.8 Ga).La majorité des âges U-Pb de la monazite constituent une seconde population formée à 1780.6 ± 4.2 Ma, ce qui est similaireLà l’âge obtenu pour la plupart des analyses Re-Os sur l’arsénopyrite (1763 ± 11 Ma). Ces âges reflètent probablement l’atteinte du pic métamorphique M2TB.La géochronologie 40Ar/39Ar de l’amphibole, de la bio"

Jan 1, 2009

The Australian Gas Light. Company was established in 1837, the first gas being sent out from the Kent Street Works, then the headquarters, in 1841. Mortlake Works were opened in 1886, and has since grown to the vast undertaking inspected by members of the Institute.The Kent Street Works were closed in 1921. The area of the, company's property at Mortlake is 117 acres.Some interesting figures from the statistics of the company's activities for 1937 are:-

Jan 1, 1938

By Reed. Donald F.

"Deposits of gray hematite occur in two districts in Talladega County, Ala., the Emauhee-Tallasochatchee and Weewoka, both in the vicinity of Winterboro, 50 miles east of Birmingham.The deposits were investigated by the Bureau of Mines in 1943 and 1944. Approximately 13,000 feet of diamond drilling was done and 6,000 linear feet of trenches excavated and sampled.A total of 13,000,000 tons of ore averaging 36 percent iron was indicated in all areas.A detailed discussion of each property investigated, drill logs, and sampling results are given in this report.In the work done in the Talladega County iron investigation, special acknowledgement is due to Paul M. Tyler, formerly regional engineer, Eastern Region, and Richard W. Smith, formerly district engineer, for aid and direction of the project; also to J. B. Clemmor, metallurgist, for diligent research work in the Southern Experiment station laboratory. All were members of the Bureau of Mines Staff.The project was conducted in cooperation with the Federal Geological Survey, whose field work was in charge of T.G. Andrews assisted by Brewster Baldwin. The able and valuable assistance of Andrews and Baldwin aided greatly in accomplishing the project.The areas investigated by the Bureau of Mines were in two districts: The Emauhee-Tallaseehatchee district, between Sylacauga and Sycamoer (marked B on fig. 1) and the Weeworka district, between Winterboro and Sycamore (marked A on fig. 1)."

Mar 1, 1949

By J. A. López-Molina, S. García, V. Castellanos-Pedroza

"Groundwater inflow into underground constructions may cause hazardous working conditions and environmental problems. It is essential to localize and characterize potential flow paths and to estimate the amount of water leakages, so that appropriate sealing works can be performed. Estimating the amount of water ingress is a multi-phase process starting from qualitative and quantitative examination of rock mass. Due to association of uncertainty, vagueness and incompleteness with the monitored data set, particularly resulted from the in situ tests, accounting relevant approaches such Fuzzy Logic and Recurrent Neural Networks, are proposed in this research for learning acquisition, extraction of rules and prediction of behaviors. The computational set of artificial tools permits using the complex information entities or information granules (rock types, geologic structures, hydro-fracture potential) for data abstraction and derivation of knowledge from records (numerical or linguistic format). This is more a theoretical perspective than a set of methods or principles. As a theoretical perspective, this proposal encourages an approach to data that recognizes and exploits the information present in indexes at various levels of resolution or scales. In this sense, it encompasses the methods which provide flexibility and adaptability in the resolution at which knowledge or information is extracted and represented. The product of merging these tools is a 3D artificial-mapping of rock classification (Qi-system), geological conditions and Lugeon units that permits, as far as possible, to understand more and better the flow behavior."

Jan 1, 2015

By Charles LeMoyne

The Cable belt Company has been building single flight conveyors for a number of years. The simple design concepts of this type conveyor, introduced over thirty years ago, when distances of one to two miles were considered major advances in technology, remain relatively unchanged. Conveyors that are 6 to 20 miles (9.0 to 32 kilometers) long are being built and are presently in operation through- out the free world. The Cable Belt conveyor is not conventional in its construction. Cable welt differs from conventional troughed idler conveyors in that the driving medium and carrying medium are separated. Motion is provided by two endless steel cables running the length of the conveyor. The cables are driven by a single drive unit incorporating a differential gear which insures identical cable linear speeds and equal tension in both cables at all times. The belting is located and supported by "V" shaped shoeforms moulded to the belt which form a wedging action. The friction between the belting and rope is sufficient to prevent slippage (See figure 01).

Jan 1, 1983

It is difficult, and probably inadvisable, to frame rigid rules for the valuation of alluvial deposits, for such deposits are very diverse in type, varying, for example, according to the mineral sought and according'to the complexity of the deposit which, on one hand, may be a narrow welldefined alluvial strip at the bottom of which is a continuous mineral lead, or, on the other, may be a broad alluvial flat with discontinuous patches of the valuable mineral occurring at different levels throughout the alluvium.However, some definite procedure in valuation must be adopted when dealing with anyone deposit, and the fundamentals of such a procedure are applicable to almost all alluvial deposits.The methods described in this paper are based very largely on the valuation of a specific deposit and, although an attempt has been made to keep the discussion as general as possible, it contains some statements which, if traced to their origin, spring from the writer's association with that deposit. Such statements must be interpreted with sufficient flexibility to be appropriate to whatever area the reader may have in mind.The subject of valuing an alluvial deposit falls naturally into two divisions: The valuation of each borehole; the valuation of the deposit as a whole. The following discussion is therefore dealt with under these two headings.Some general matters are mentioned in a third section.

Jan 1, 1950

By D. R. Wilburn

The worldwide budget for nonferrous, nonfuel mineral exploration was expected to increase by 58 percent in 2004 from the 2003 budget, according to Metals Economics Group (MEG) of Halifax, Nova Scotia. The increase comes two years after a five-year period of declining spending for mineral exploration (1998 to2002). Figures suggest a subsequent 27 percent increase in budgeted expenditures from 2002 to 2003. For the second consecutive year, all regional exploration budget estimates were anticipated to increase. The worldwide budget for gold exploration achieved about 50 percent of the total amount budgeted in 2004.This was 68 percent, or US$715 million, higher than the reported 2003 budget. The 2004 worldwide exploration budget estimates for copper increased by 70 percent, orUS$237 million, to US$577 million from the 2003 budget. The budget for nickel exploration increased 52 percent, or US$89 million more than in 2003. The 2004 exploration budget for other mineral targets (primarily cobalt, heavy minerals, industrial minerals and silver) increased114 percent, or US$118 million.

Jan 1, 2005

By Herbert H. Kellogg

The chemistry of sulfide roasting is analyzed to show those aspects of performance which Thecan be predicted from considerations of thermodynamic equilibrium. It is concluded that equilibrium calculations can serve as a yardstick for prediction of roaster-gas composition and sulfate formation in the calcine for fluid-bed roasting practice. A method of calculation which combines the equilibrium and stoichiometric factors is outlined, and illustrated by an example from the roasting of Cu-Fe sulfides. ON first examination the roasting of sulfides would not seem to be a process to which equilibrium calculations could be applied to yield results of practical value. The burning of sulfides is an ex-tremely spontaneous reaction, excess air is always used to obtain rapid reaction, and in most traditional roaster designs (hearth roasting) the temperature and gas composition vary widely from point to point in the roaster. These are all conditions which promote a non-equilibrium state in the roasting process. However, the introduction of the fluid-bed roaster1 has brought to roasting practice new conditions of operation, so that equilibrium calculations can be used to predict certain limited aspects of practical operation. The fluid bed is characterized by uniformity of temperature, gas composition, and calcine composition from point to point throughout the bed. These relatively uniform properties of the bed make the meaningful calculation of the equilibrium state of certain reactions in roasting possible. It is the purpose of this paper to analyze roasting from an equilibrium viewpoint, to show where the method may be expected to yield valuable information, where it fails, and to outline methods of calculation. Main Roasting Reaction The reaction MS (s) + 3/2 0, = MO (s) + SO, [I] might well be called the main roasting reaction. It adequately accounts for the well known facts that metal sulfide and air are the main reactants, and metal oxide and SO, the main products. Deviations from this simple stoichiometry will be discussed under side reactions. For all metal sulfides, Reaction 1 is strongly exothermic and the equilibrium position is far to the right. Since the reaction is exothermic, the equilibrium shifts in the right-to-left direction as the temperature is raised. However, at all practical roaster temperatures (between 500" and 1200°C), the amount of this shift is small, and the equilibrium position remains far to the right. The main roasting reaction is essentially irreversible, and the application of equilibrium considerations to this reaction will not be! a fruitful field of investigation. A knowledge of the rate of this reaction. although not the proper subject of this paper, is of great importance to the roasting process. Analysis of the factors which influence this rate shows that: 1) The rate will increase rapidly with increased temperature. 2) The rate will be proportional to the partial pressure of oxygen at the surface of the reacting particle. Because of diffusion effects, the partial pressure of oxygen at the particle surface may be considerably less than in the bulk of the roaster gas. For this reason, intimate contact between gas and solid and high relative velocity between gas and solid, such as can be obtained in a fluid bed or flash roaster, will markedly increase the rate of reaction. 3) The rate will be proportional to the surface area of metal sulfide. Therefore, smaller particle size will permit a more rapid rate per unit of weight. To achieve practical rates of roasting the partial pressure of oxygen in the roaster gases must be maintained at a finite level at all times. Even where the gas-solid contact is very good, as in the fluid-bed roaster, the oxygen content of the gas must not be allowed to drop below some limiting value (perhaps 1 pct), or the rate of the main roasting reaction will become too small for practical operation. Side Reactions in the Gas Phase The gas phase during roasting of metallic sulfides contains the elements oxygen, sulfur, nitrogen, by-

Jan 1, 1957

By Don K. Smith

The Reclamation Program for the Northern Zone of the Indus Plains in West Pakistan involves the construction of 30,000 irrigation wells to serve 20 million acres with an annual pumpage of nearly 40 million acre-ft. Detailed hydrologic studies indicated that mild steel would be satisfactory for casing; however, within two years after construction, about 10% of the wells began to fail due to encrustation and corrosion of the casing. A search to find a noncor-rosive substitute for the steel casing disclosed that only fiberglass-reinforced plastic pipe satisfied all requirements. The results of initial use of fiberglass have been highly satisfactory and have resulted in a lower over-all well cost. Advances in technology pomise further reduction in prices and improvement in performance. The northern zone of the Indus Basin comprises a vast area of essentially level land in West Pakistan which is irrigated by means of a complex system of canals that distribute more water to more land than any other irrigation system in the world. In spite of the development of this extensive irrigation system, production of food and fiber has not met the requirements of the country. The major reasons that crop production has not reached anticipated levels are the lack of adequate irrigation supplies and effective subsurface drainage. As a result, yields per acre are among the lowest in the world for areas where irrigation is practiced, and many thousands of acres of valuable crop land have been removed from production or seriously affected by salinity and waterlogging. To rectify the problems of irrigation supply and drainage the Government of Pakistan has undertaken a program of Salinity Control and Reclamation which is being administered by the Water and Power Development Authority. The Authority retained Tipton and Kalmbach, Inc., of Denver, Colo., as engineers for the program in the northern zone of the Indus Basin. This program consists of the construction of about 30,000 irrigation wells to provide drainage for waterlogged lands and full irrigation supplies, including leaching requirements, for all cultivated lands. The program will ultimately ensure the productivity of 20 million acres and involve an annual pumpage from groundwater storage of nearly 40 million acre-ft of

Jan 1, 1970

By M. A. Trevits, M. R. Thibou, A. Ozment, A. C. Smith, J. B. Walsh

The Excel No. 3 Mine is a room-and-pillar mining operation owned by MC Mining, LLC, a subsidiary of Alliance Resource Partners, LP, which produces coal from the Pond Creek Coalbed in Pike County, Kentucky. Late on December 25, 2004, a fire was discovered near the bottom of the slope and, after an unsuccessful attempt to fight the fire underground, it was decided to address the fire remotely from the surface. The mine operator developed a plan to fight the fire that called for the installation of temporary seals at the slope and mine shafts to eliminate the inflow of oxygen. In addition, the plan called for drilling and completion of vertical boreholes into select areas of the mine workings to monitor the mine atmosphere and inject nitrogen gas and gas-enhanced foam. Over the next 9 days, nitrogen gas was injected almost continuously and gas-enhanced foam was injected periodically as deemed necessary. On January 7, 2005 it was determined that the fire was successfully suppressed. This paper presents a discussion of the fire-fighting approach and an analysis of the results of the application of gas-enhanced foam technology.

By M. L. Tucker, William H. Langer

Many countries, provinces, territories and states in the European Union, Australia, Canada, the United States and elsewhere have begun implementing sustainability programs. Most of those programs, however, stop short of sustainable management of aggregate resources. Sustainable practices do not always have to be conducted under the title of sustainability. This case study describes how Lafarge implemented the principles of sustainability even though there was an absence of existing local government policies or procedures addressing sustainable resource management. Jefferson County is one of three counties in the six-county Denver, CO, region that has potentially available sources of crushed stone. Crushed stone comprises 30percent of the aggregate produced in the area. And it plays a major role in regional aggregate resource needs. Jefferson County is home to four of the five crushed stone operations in the Denver region. Lafarge operates one of those four quarries.

Jan 1, 2004