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By A. Darragh

"Past Growth The Canadian coal industry has grown rapidly during the past two decades. Coal production increased over four-fold between 1965 and 1982; consumption almost doubled, imports remained relatively flat, exports soared and total demand increased nearly two and a half times. Coal production grew during this period at an average rate of 8.60/o, compounded annually; this remarkable performance is shown in Table 1 and Figure 1. The relationship between production and consumption is shown in Figure 1, where in 1981 the total Canadian production of coal for the first time exceeded total Canadian consumption. ln Figure 2, the relationship between imports from the United States and Canadian coal exports is shown; in_ 1981 again for the first time, exports offshore exceeded imports into Canada. The rapid growth in Canadian coal use between 1965 and 1982 followed a major decline after World War II, as the country moved rapidly to an oil based economy. Changes in consumption patterns between 1945 and 1982 are shown ~n Table 2. Railway consumption of coal was reduced to zero m the early 1960s. The industrial and domestic consumers market share fell from about 660/o in 1960 to 6.70/o in 1975; this share, however, appears to have stabilized in recent years and actual volumes can be expected to increase in the future. The steel industry's share of the coal market fell over the same period, but the volume in recent years has remained fairly constant at about seven megatonnes per year.Perhaps the most significant change in consumption is in the share of coal consumed in the generation of electricity; this has increased from 80/o in 1960 to over three quarters of the total Canadian coal consumed in 1982. This increase in thermal coal consumption has been supplied by indigenous coal, and was accompanied by a decreasing share for coal imported from the U.S.A. into central Canada. It is expected, because of the nuclear power commitment in Ontario, that this share will continue to decrease, although the total volume of coal imported may increase slowly over time. This will likely also have a dampening effect on future coal sales to Ontario from western Canada."

Jan 1, 1985

By W. Cholewa, T. S. Golosinski, J. Wedzicha

"Power requirements of belt conveyor drives are usually estimated based on the calculated belt tension which equals the sum of unit resistances to motion which the belt has to overcome. In most situations, the value of various unit resistances can be accurately predicted using published information (5,6,8,12). A simpler approach calls for use of standard formula and tabulated values of related factors which reflect various features of both the conveyor and the transported material (2,3,7) . None of these approaches is reliable when materials with unique properties are conveyed, nor if applied to conveyors working in extreme climatic conditions. Such is the case of oil sand mines in northern Alberta.There the bitumen content of oil sand causes it to behave in a unique manner. Furthermore the conveyors operate year around, with winter temperatures often lower than - 40°C. It was the objective of presented investigations to quantify the power requirements of conveyors, and related resistance to motion for the conveyors used in oil sand mines during winter operations.The other objective was to quantify the drive power requirements of oil sand conveyors during start-up. These requirements are usually much higher than those during norm al operation, and their quantification is of paramount importance for operation of large conveyors."

Jan 1, 1992

By H. H. Gardner

Introduction The Greenhill mine of West Canadian Collieries, Limited, is on the Alberta side of the Crowsnest pass, twelve miles from the Alberta British Columbia boundary-line. Here, five coal seams of Lower Cretaceous age are found in the Kootenay formation. They outcrop on the north and south slopes of the valley, with strike approximately N.30°W., paralleling the main range of the Rocky mountains, and dip about 40 deg. westward. Of the five seams, only two, designated No. 1 and No. 2, have been worked to date. On the West Canadian Collieries property, No. 1 seam ranges in thickness from thirty feet to nil. Generally, it has a hard, strong conglomerate roof. No. 2 seam is separated from No. 1 by forty-five feet of shales and sandstones. It has a thickness of eight to thirty feet.

Jan 1, 1947

By Bob A. Hamaguchi

The Trojan Tailings Pond at Highland Valley Copper developed in only 15 years from a biologically inactive water body into a productive lake with a well established aquatic ecosystem. This process was assisted by a few simple and inexpensive procedures including fertilization and introduction of essential organisms. The success at the Trojan Pond has encouraged the use of similar techniques in other water bodies on the mine site. This paper details: ??The history, water quality and thermal behavior of Trojan Tailings Pond ?Techniques used in fertilization; introduction of micro-flora (algae etc.), large aquatic plants, zooplankton and invertebrates ??Selection and sources of suitable transplant materials ??Rate and extent of vegetation establishment ??Biomass production ??Rates of organic sediment accumulation over tailings ??Bacterial activity in the sediments ??Improved water quality through the bioaccumulation of aqueous metals in plants and the subsequent bacterial binding or precipitation of that metal during decomposition in the tailings sediment. Robert A. Hamaguchi graduated with a Mining Diploma from the British Columbia Institute of Technology in 1971, followed with a Bachelor of Applied Science in Mineral Engineering from the University of British Columbia in 1975. Since graduation, he has worked for numerous open pit mining operations throughout British Columbia. In 1991, he joined Highland Valley Copper working as an Environmental Engineer responsible for government liaison, reclamation, decommissioning and other environmental duties. Heather M. Larratt graduated from the University of Calgary in 1978 with a B.Sc. in Environmental Biology (First Class Honors). She has provided drinking water management and reservoir design for numerous cities and irrigation districts in British Columbia for 20 years. Heather has also worked for 12 years in reclamation of mine water, including passive SRB water treatment systems. Mark R. Freberg joined Highland Valley Copper in 1991 after working at number of mining operations in British Columbia and the Northwest Territories. He graduated in 1979 with a Bachelor of Applied Science degree in Mineral Engineering from the University of British Columbia.

May 1, 2001

By A. T. GRIFFIS, R. J. GRIFFIS

A large magnesite-talc body is locared in Delora Township, 11 km sourh-southeasr of Timmins, Onrario. The deposit occurs in part of an Archean greensrone belt dominated by volcanic and sedimenrary rocks and large bodies of ultramafic intrusions. The magnesite-talc zane is abour 1800 m long, has a maximum width of 300 m and has been drilled ro 120 m below surface. Chemical analyses of rhe main carbonate zane average 20 ro 28% soluble MgO (magnesia), 5 ro 6% rota/ iron oxide and less rhan 0.1 % CaO (lime). Mineralogically, the zane consists of approximately 54% magnesite, 28% rate, /5% quartz and 3% hematire. Perrographic srudies suggest that rhe various assemblages of magnesite, rate, quartz and serpentine were derived from a parenr serpenrinire (after dunire). An early carbonitization stage, which produced a high-magnesite, low-talc assemblage, preceded a farer decarbonitizarion stage, which formed rhe main magnesite-talc assemblage. Despite a favourably low calcium oxide content of rhe magnesite-talc rock, considerable iron in the magnesire /at rice has limited the quality of the beneficiared product: rhe besr flotation concentrate to dare yields 92 to 94% dead-burned MgO. Experimen- I L t r i i c:~:.•-4- -------- ? -_;> ,•----1---- ta/ work continues on finding a process whereby high-purity magnesia can be produced on a commercial scale.

Jan 1, 1984

By Y. P. Wu

Steeply dipping seam refers to the coal seam with dipping angle in the range of 35?55°, which is well recognized to be very hard to mine by the mining industry all the world. In the last two decades, some fundamental researches were focused on the strata behavior of long-wall panel, complicated rock mass breaking process of the steeply dipping seam, overburden stress field developing and evolution, rock strata breaking and moving process, rock structure stability mechanism and control. Results show that it?s presenting macro stress arch-shell (MSAS) of the stress distribution of the overlying rock in steeply dipping seam. The MSAS is the spatial distribution of intensity envelope line under the strength criterion and has the geometry shape asymmetry as well as the stress distribution heterogeneity. The arch- shell base will forward as the working face mine forward and the shell roof will extend to higher overlying strata above the gob. In this paper, the stress arch-shell analysis model and coordinate system were established and analyzed the inclined masonry structure at different zone. Analysis results show that the rock damage at the key part of the arch-shell is the main factor which causes whole overlying rock structure failure. The rock structure instability modes have tension instability of the shell roof, compression-shear instability of the shell shoulder and composite instability of the shell base, meantime, instability coefficient is proposed to determine instability condition. The above research results enrich the complex coal seams mining theory and provide a theoretical basis for mining safely and efficiently in steeply dipping seam.

Aug 1, 2013

By G. A. Buckland

"The development, in Ontario, of a common industry-wide program for the development of skills for employees in underground hard-rock mining is described. This program is designed to increase the productivity of individual workers by improving their skill levels, while at the same time ensuring that employees are instructed in the requisite safety and health aspects of performing various underground tasks. The program's development through a management-labour-government tripartite approach is described. How this program was coordinated with new Government Regulations on Occupational Health and Safety dealing with mandatory training of underground employees is also outlined. IntroductionThis paper will describe briefly what modular training is all about and outline why, and how, it was developed in Ontario on an industry-wide basis. Simply stated, what's been accomplished to date is an industry-wide program for developing the mining skills of underground production employees.The basic objective of this program is to improve the productivity of underground workers. It involves developing an employee's skills to improve his productivity and, because working productively involves knowing how to do a job safely, the program includes instructing an employee in the various safety and health aspects of underground work. An important and, I believe, distinguishing point about the development of this program is that it has been done with the full participation, cooperation and commitment of management, labour and government.It's of considerable interest to note that companies in Ontario who are now using this program are finding that new employees are approximately six months further advanced in productivity than was the case before its use, and in some cases the frequency of accidents has shown a reduction among those employees who have taken this program as compared to those who haven't"

Jan 1, 1980

The problem of thin and very thin coal seam extraction in a long perspective of Ukraine?s fuel and energy industry development was determined. Technical and economic benefits of coal seams selective mining technique including beneficial environmental impact were substantiated. The scientific and practical aspects of development of borehole underground coal gasification (BUCG) technology are considered. The technological scheme of underground gas generators is offered on the basis of the authors? criteria of fitness and adaptability to the mine and geological conditions. These charts foresee the preparation of gas generators from earth surface and directly from the present mine working by inclined horizontal boreholes. Basic research is directed at abandoned supplies extraction in coal mines. Concepts of technological decisions and technical implementation of the underground part of the gasification system are worked out with analytical models, with subsequent test verification on special options and a mine experimental gas generator. Forming the technological scheme of gasification is founded on the basis of tying up spatial and sentinel factosr of coal seam gasification taking into account sufficient impermeability of the system a «gas generator ? rock massif» and to dirigibility by thermochemical processes that flow in a rock massif. The offered solutions contain the possibility of creation of the power and chemical enterprises of gasification, taking into account the complex use of BUCG products in the ecologically reserved technological cycle. Gas generator efficiency is evaluated from an economic standpoint.

Aug 1, 2013

By L. B. Kilius

The composite cathode system based on Ce0.9Gdo.1O2_,5 electrolyte with a painted cathode was used for an intermediate temperature (500-700°C) solid oxide fuel cell. This cathode system was chosen due to its excellent thermal expansion match to the electrolyte, its relatively high conductivity (115 S cm-1 at 700°C), and its low activation energy for oxygen reduction (99 kJ/mol). It was found that the decrease of sintering temperature of the composite cathode system produces a significant decrease in charge transfer resistances to a level of 0.25 SI cm2. The conductivity measurements of porous samples produced values between 40 and 88 S/cm for porosities of 30-40%.

Jan 1, 2005

By Cheryl Devine, Radhakrishnan Mahadevan, Vladimiros G. Papangelakis, Srinath Garg

The microbial-mediated recovery of valuable metals locked in mining wastes presents an economical alternative to conventional hydrometallurgical processes. The present study investigated the bioleaching response of a low-grade nickeliferous pyrrhotite tailings (0.6 wt% Ni) and an upgraded pyrrhotite tailings (1 wt% Ni) produced by Vale Base Metals in the Sudbury Basin of Ontario, with the ultimate aim of maximizing Ni recovery. The initial part of the study focused on the bacterial adaptive evolution protocol, by repeatedly sub-culturing an indigenous culture from an acid mine drainage site on 2% (w/v) pyrrhotite tailings. The results showed that the extent of Ni dissolution is positively correlated with microbial activity. Microbial profiling revealed A. ferroxidans to be the dominant member of the microbial consortium. The enriched culture was used for optimizing the growth medium by varying the concentration of essential growth nutrients. Finally, an aerated biotic and abiotic leach of a 10% (w/v) upgraded pyrrhotite tailings with and without pH control, showed a higher recovery of Ni in the pH controlled experiments. These results demonstrate that a high concentration of the oxidant Fe3+ in solution promotes the dissolution of Ni. Furthermore, the sulphide conversion into So was found to be higher in the pH controlled experiments (32%), relative to the experiment without pH control (10%).

Jan 1, 2015

By J. Dilbeck, J. K. Ratliff, T. Petrov, Z. Brown

"In efforts to improve dust control during deep cut continuous mining a supplemental atomizing spray system, mounted on 14CM15 continuous miner, has been designed and successfully implemented in a U.S. coal mine. The mine is 2.1 m (7-ft) high and uses a blowing curtain face ventilation system with 1.1 m (3.5-ft) curtain offset from the rib. The face ventilation design parameters were set to 9.4 m3/s (20,000-cfm); 4.2 m3/s (9,000-cfm) line curtain flow rate, and 3.8 m3/s (8,000-cfm) scrubber capacity. The performed in-mine measurements, before and after the implementation of the atomizing spray system, showed a significant decrease in the respirable dust levels at the operator place as well as at the return. The paper describes the supplemental water spray system design and performance supported by three-dimensional computational fluid dynamics (CFD) simulations and in-mine test data.INTRODUCTIONThe work on this project have started in 2015 with a study of the conventionally applied face ventilation layouts. The specific behaviour of the face ventilation system have been analyzed trough in-mine measurements and computer modeling of typical cut scenarios. An computer modeling methodology have been developed for estimation the respirable dust concentration (RDC) using tracer gas to RDC contour mapping, calibrated by a single point value, provided by in-mine measurement. Utilizing the results of this study the engineering staff of the mine designed and implemented a supplemental atomizing spray system to improve the dust control during the deep cut continuous mining. Today the atomized spray system is successfully applied demonstrating steady performance and a significant decrease in respirable dust concentration on the working places of the continuous miner (CM) and coal transporters (CT) operators as well as at the return air stream. Information about the applied type of spray nozzles provided by other researchers (Cheng, 1973; Dick et al., 1996; Organiscak & Page, 1998; Pollock & Organiscak, 2007) and spray system manufacturers (Spraying System Co, 2011–2018; Steinen Mfg., 2016) have been used in this project. CFD code and simulation approach validated in a study conducted in 2000-2014 have been applied (Turner et al., 2002; Wala et al., 2004, 2007; Petrov, 2014)."

Jan 1, 2019

By R. W. Boyle, W. Dyck

"Scientists throughout the world have observed radioactive disequilibrium in the uranium decay series. Radiometric and fluorometric determinations of U in plants from the Goldfields district and in sediments and rocks from the Beaverlodge district exhibit marked radioactive disequilibrium. The eU/U ratio in plants rooted in mineralized ground shifts from greater than unity to less than unity for those rooted in background soils. A similar shift is observed in the transition from rocks to stream sediments and to lake sediments in the Beaverlodge district.Results of a Rn-Ra-U survey of lake bottoms in the Key Lake district show that anomalous hydromorphic U from U mineralization is parallelled by anomalous Rn, even though there is much less Ra in the lake-bottom sediments than one would expect from the amount of U present. IntroductionDisequilibrium in the U decay series has been studied for many years and is observed in almost all surficial environments. Rosholt (1959) measured U, 234Pa, 23O'fh, 226Ra, 222Rn, and 210Pb in a large number of U ores and outlined six types of situations to explain disequilibrium. Davy (1974) outlines the geological significance of radioactive disequilibrium situations with respect to exploration. Levinson and Coetzee (1978) discuss possible mechanisms by which separations of parent and daughter elements are affected and suggest analytical pitfalls that may be encountered in the use of radiometric techniques when disequilibrium has occurred. Generally, it is the oxyphile and easily complexed parent 238U (with its associated isotopes 235 U and 234U) that is leached from rocks and soils at a faster rate than are the daughters, 230Th, 226Ra, 2loPb, and 206Pb. This mobilized U is adsorbed on sediments in streams and lakes, or enters groundwaters, where it is eventually precipitated under reducing conditions, occasionally in oregrade concentrations. This surface leaching and"

Jan 1, 1980

By E. P. Wiechrnann, C. M. Castro, G. A. Vidal, F. A. Muñoz

Different authors and publications indicate that Optibar Segmented Intercell Bars cause a remarkable distortion in the distribution of the current in a cell group. However, these results were based in inaccurate computer based models and do not represent the technology. During the last trimester of 2010, a 92 cells circuit from Barrick Zaldívar EW plant was implemented with Optibar Segmented Intercell Bars. The technology was incorporated progressively without disrupting the plant production. Depending on operational conditions, this led to a 2 to 4% current efficiency increase and 3 to 5% specific energy consumption reduction. By October 2011, 40,000 tons of copper will be produced with the technology.

Jan 1, 2011

By R. Browner, J. Collard, D. Ibana

The extraction of cobalt from synthetic pressure acid leach solutions of nickel laterite ores by the direct solvent extraction route using ESPLIM is reported. It first explored the use of gaseous ammonia as pH modifier and then the variables that affect the dispersion of the aqueous phase in the organic phase such as ionic strength, viscosity of the phases, initial droplet size, etc. were explored so that phase hold-up and thus extraction can be effectively controlled. The results show that the technique allows better control of phase dispersion circumventing one of the main weaknesses of conventional solvent extraction.

Jan 1, 2005

By M. Piboule et J. M . Charbonneau, C. Picard

In the western part of the Chapais syncline (Abitibi-east, Quebec), the lava flows belonging to the Haliy Formation separate in two distinct sequences. The basal sequence contains prophyri tic metabasalts of calc-alkaline af f inity overlain by porphyritic metatrachyandesites and metatrachytes of alkaline to shoshonitic affinity. The upper sequence contains porphyritic metabasalts similar to those of the basal sequence along with highly potassic metaandesites trending to a subalkaline affinity. A geochemical study of trace and REE elements established that the composition of these lava flows results from a mixing or contamination process. The primitive tholeiitic liquids which are enriched in LREE were modified by the addition of a crustal contaminant enriched in Y, Zr, Th and K20. The magmatic liquids resulted from successive steps in the admixing process, evolved by fractionated crystallization. The mechanism of gradual admixing seems to be the major cause of the observed ea le-alkaline characteris ties and may also be the cause of the alkaline to shoshoni tic affinity in those lavas. The tendency to differentiation by fractional crystallization reveals the tholeiitic character of the primitive liquids.

Jan 1, 1984

By H. A. Kee

In the mining industry, as in other business, one of the more satisfactory results of sincere but cheerful effort lies in the proper completion of undertakings and problems, which, to be successful, must continually hold the interest of all concerned in the work. In most undertakings, genuine interest and satisfaction is largely dependent on the proper appraisal of opportunities presented, and the opportunity to associate ourselves with sinking operations at McIntyre central shaft, from the surface to a depth of 4,133 feet, was genuinely appreciated. This opportunity was made possible by the previous persistent and successful leadership of Mr. J. P. Bickell, President, with the assistance of his associates, and of the general manager, Mr. R.J. Ennis, in the development of the McIntyre Porcupine mine, and I beg to state that any success in this sinking operation was very largely due to the congenial co-operation and splendid workmanship of Captain Martin C. Horne, his shift bosses, leaders, and all those who worked with us . Our slogan throughout was " Safety First for Pleasant and Efficient Workmanship," and this general policy made it possible to sink and timber 2.,123 feet during the first year without a serious accident.

Jan 1, 1928

The Bluebell mine of The Consolidated Mining and Smelting Company of Canada Limited extends under Kootenay lake, in southern British Columbia, and water control underground has always been a major problem. This paper gives a brief history of the operation, and then de-scribes the methods used by Cominco to keep the combination of lake seepage, ground water and thermal spring water under control. The pumping arrangements are de-scribed in considerable detail, with illustrations to show the various stages of development, and the power supply sys-tem is outlined.

Jan 1, 1966

By G. Bimpilas, G. N. Anastassakis

"Today, one of the most intense problems in mineral processing systems is referred to the treatment of fine (–100 µm), and even smaller size, particles. Fine mineral particles possess specific properties (small mass, high specific surface area, and high surface energy per unit area) that render their separation inefficient with conventional methods (physical, physicochemical) and equipment. As a result, it is not feasible to obtain a concentrate both of high grade and recovery in mineral value and a considerable amount of mineral fine particles is lost to the tailings. As evidence, we could cite numerous examples from industrial practice with considerable loss of mineral values to the tailings because of the fine particles size, e.g. phosphate, tungsten, tin, etc.The objective of the current paper is to investigate the possibility to separate magnetic gangue minerals and rocks (serpentine, ilmenite, and olivine) from magnesite by co-agglomerating all the gangue components and subsequent magnetic separation of the agglomerates.To meet the target, hydrophobic agglomeration tests were initially carried out on single minerals to define the favorable conditions for selective hydrophobic co-agglomeration of the gangue minerals. In this respect, the effect of the following factors was examined: pH, collector dose, conditioning time, and settling time of the agglomerates. Among the combinations examined, the most favorable proved that with amine in the basic pH region. The use of non-polar oil proved beneficial. The preliminary results were confirmed by tests on mineral mixtures. The application of magnetic separation resulted in the removal of gangue minerals and the recovery of magnesite concentrates of commercial grade (magnesite content 95% approximately) and high yield.The current paper contributes to the development of mineral processing, since it successfully copes with a very important problem of mineral processing, such as the efficient separation of fine particles."

Jan 1, 2016

By Robert D. Brown

"The Conservative Government 's budget proposals brought forward on December 11, 1979 have been withdrawn, but they are far from dead. On the contrary, a number of those budget proposals, especially the ones which would close loopholes and result in other technical changes being made to the Income Tax Act, should be considered to be alive and well.It is not unreasonable to expect the next government, of whatever political persuasion, to reintroduce many of these technical changes in the next federal budget. For that reason, last December's budget may have offered an interesting preview of what the mining industry and other taxpayers can expect in 1980. It is quite possible that some of these changes may be effective as of the original dates announced in the withdrawn budget proposals.This month, ""Tax Notes"" reviews the main pro visions of Mr. Crosbie's December, 1979 budget, with a primary focus on the changes that would have affected the resource sector.It must be emphasized that all of the budget proposals discussed herein have been withdrawn, that none of them are law and that any actual changes in our tax rules will have to be dealt with by the new Parliament that will be assembled following the February 18 election. December 1979budget withdrawnThe federal budget proposals brought forward by Finance Minister John Crosbie on December II, 1979 were withdrawn as a result of the defeat of the Conservative Government on a motion of non-confidence in the House of Commons on December 13. However, it appears quite possible that at least some of the proposals may be introduced into Parliament at a future date, possibly with retroactive effect.In a press release issued by the Department of Finance, Finance Minister John Crosbie stated that if the Conservative Government is returned to power, it will reintroduce all of the measures contained in his December II budget.Mr. Crosbie stated that all of the income tax measures contained in the budget would be reintroduced, effective on the dates indicated in the Notice of Ways and Means Motion tabled on December II. Some of the more important measures in December II budget, and their effective dates as indicated in the Notice of Ways and Means Motion, are discussed below.The December budget had also introduced or increased excise taxes or duties on gasoline, wines, cosmetics and photofinishing. If the Conservative party is re-elected, these measures will be reintroduced with prospective effect (i.e . effective as of new dates to be announced in the new budget)."

Jan 1, 1980

By M. Marchese

It is no secret that scarcity of fresh water is an issue that at a global level in the years to come will have a major impact on the business landscape. A number of projects, beyond the mining sector, could remain on paper only due to this. At the same time, this situation is seeing the rise of new business opportunities, such as development of technologies for more efficient usage of water, water recycling, and desalinization of sea water. Despite that most of Chilean mining facilities are located in the driest area of the world, business has developed strongly and actively for more than a century. However, the negative effect on the water reservoirs and the environment is, lately, resulting in the reduction of the authorized water rights. Holding Water Rights for any given volume does not guarantee that the resource will be available when needed. A recent report from the United Nations on global climate change indicates that global warming can be directly related to changes in the natural and human environment. Chile would not be an exception. The reduction in snow levels in the high Andes and reduced rainfall during the so called "Bolivian winter", have directly affected the replenishing of the underground water reservoirs in the lower parts of the valleys, where most of the extraction of the resource takes place. Mining facilities shall be designed to reduce potential environmental effects, using proven technologies, and considering the best practices available. These measures shall constitute a complete structural framework for the environmental impact assessment (EIA) of the Project. The measures to prevent and mitigate the impacts on the water resources shall be considered during the design stage of a mining project. Current and future mining projects in Chile are conscious that the increasing pressure on the limited water resources is becoming unsustainable, and are already facing the water scarcity and social pressure by implementing sea water desalination plants, including long pressurized pipelines to the mine sites (e.g. Escondida, Candelaria, El Morro, Regalito). This paper presents, in summary, an analysis of the present and potential future scenarios.

Jan 1, 2007