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By L. L. Gagné

The Churchill Falls Development will eventually be the largest source of hydroelectric power in North America. Churchill Falls was discovered in 1839, but until recent years it was not practical to begin development of this site to tap the 7 million horsepower available. This $1 billion project is located in Labrador, 700 miles northeast of Montreal and 650 miles northwest of St. Johns, Nfld. The construction will divert the Churchill River 5 miles upstream from the 245 foot Churchill Falls. Rapids above and below the Falls, together with the Falls proper, give a natural head of 1,040 feet. In contrast to the basic simplicity of the surface installations, the powerhouse labyrinth is astounding in size and complexity. The largest in the world, it consists of three major chambers - the powerhouse, 972 feet long by 81 feet wide and 154 feet high; the surge chamber, 763 feet long, 40 feet to 64 feet wide and 148 feet high; and the transformer gallery, 856 feet long by 50 feet wide and 39 feet high. Other major features include eleven inclined penstocks, each 1200 feet long and 20 feet in finished diameter; eleven draft tubes averaging 37 feet in finished diameter and 162 feet long; six vertical cable shafts each an average of 865 feet in length; a series of eleven short bus tunnels linking the powerhouse and the transformer gallery; a vertical power-

Jan 1, 1997

By Mike Horn, Keith Meade, Marvin L. Smallwood

Technological changes in programmable logic controllers (PLC)'s and the need to improve the architecture of Mine Wide Monitoring Systems (MWMS) has resulted in the design of a PLC based system at the Virginia Division of Island Creek Coal Company. The system which is presently in the installation phase, is a joint effort of Island Creek Coal Company, Westinghouse Electric Supply Company and Mining Controls Incorporated. The system uses an ethernet based network for graphic display of system data operating under the Genesis software package. Telemetry for the system utilizes the Seimens/Westinghouse L1 network operating over two twisted pairs. Remote telemetry uses fiber optic links and modems operating over standard telephone lines. 500 and 2000 series PLC's provide distributed data processing for the system with hierarchial processing operating under the Genesis software on the ethernet network for individual mine site monitoring along with the remotely located division office monitoring. System control and data acquisition is provided for underground MWMS operations and on the surface for a vast methane gathering system that is used for degasification of the mines and collection of pure methane for sale to the Columbia Gas Company as natural gas. The inability of industrial MWMS companies to keep up with the vast changes in technology, along with economic considerations associated with expanding the existing MWMS created the need for the development of the PLC based system to replace the older industrial monitoring systems.

Jan 1, 1993

By R. C. Bryan, D. B. Jamison

This paper describes a procedure for minimizing the operational costs associated with blending sodium in coal at a surface mine in the Powder River Basin. Mine site blending is performed by adjusting daily production rates for high- and low-sodium pits. These adjustments are designed to produce a consistent sodium value called the blending target. The mine's contractual limit for sodium is sufficiently close to the field average value that any decrease in the sodium blending target may result in an opportunity cost, if the number of potentially minable tons is reduced. Conversely, any increase in the blending target may result in a higher sampling cost if more information is required to keep the blend within contractual limits. Blending parameters were defined using a geostatistical block model of sodium content that was based on analyses of hundreds of in-pit sample holes. Variograms for these data were used to compute the marginal costs of opportunity and sampling for a series of hypothetical in-pit drilling patterns. These marginal costs provided a basis for selecting optimum values for key parameters such as the blending target, production variance and in-pit sampling density. The benefit of implementing these optimized parameter values is that operational costs of sodium blending will be minimized over the long-term. At the mine where this procedure was developed, each dollar spent to increase the sampling density to the optimum value was shown to generate a $10 savings in opportunity cost.

Jan 1, 1991

By G. Bryant, P. Ziemkiewicz

Acid mine drainage (AMD) from both abandoned surface and underground mines is a serious problem. The flow of water and changes in quality over time from abandoned mines is important in determining remediation strategies. Acid mine drainage from surface mines is estimated to last for 10-20 years, while estimates of acid drainage from underground mines vary from 10- 100s of years. Fifteen underground mine discharges in West Virginia were studied to compare water quality changes between 1968 and 1999 to see if our data are consistent with other studies. Each of the discharges were categorized into one of three groups: undisturbed since 1968, affected by surface mining since 1968, and reclaimed. Comparing water quality between 1968 and 1999, the discharges in the undisturbed category showed a 35 to 95% improvement in acid concentration and a 40 to 99% reduction in iron concentration. The discharges affected by surface mining showed the most dramatic improvement. For acidity, iron, and aluminum, the percent improvements were all above 44%, and in most cases in the 70 to 99% range. In the reclaimed category, one of the four discharges declined in water quality. Discharge 82 showed a 76% increase in acidity, and iron and aluminum concentrations worsened by 58 and 96%. However, discharges 15 and 74 improved in water quality with a 94% acid load improvement and a 95% iron load improvement at both sites.

Jan 1, 2000

By Joseph M. Denk, John N. Baran, William J. Francart

Filling or sealing shafts of underground coal mines is required when the mine is declared inactive by the operator, permanently closed or abandoned for a period of time greater than 90 days. Although shaft filling requires the use of incombustible materials for the first fifty feet of the shaft, a sparking potential may exist which has been reported to be the cause in at least one shaft-filling explosion. This paper outlines the method used at the explosion site to monitor mine gases within the shaft to assure the safety of the workers involved in the remainder of the shaft-filling operations. Gases which were monitored include methane, oxygen, carbon monoxide and carbon dioxide. Continuous sampling was conducted twenty-four hours per day to determine the methane liberation and accumulation of gases within the shaft. Once gas concentrations were evaluated, the need for ventilation in the shaft was obvious because methane accumulations within the shaft were in the explosive range. Several methods to ventilate the shaft were explored. The most practical seemed to be the dilution of gas concentrations with compressed air to inject a quantity of fresh air into the shaft. But, when the compressed air was stopped, a buildup of an explosive mixture reoccurred. The pattern of gas accumulation was then studied to find the correct combination of ventilation and shaft-filling time periods which would a1 low for the greatest reduction of the potential for an explosion. Gas concentration sampling continued during the remainder of shaft-filling operations at this shaft and four others at the same mine. In conclusion, this paper illustrates some of the problems which are often overlooked in a shaft-filling operation. If addressed, the work can be done in a safe and feasible manner.

Jan 1, 1987

By William G. Doepken

After 15 years of production, 91 Mt (100 million st) of ore mined and nearly 227 kt (500 million lb) of molybdenum produced, Climax Molybdenum Co.'s Henderson Mine and Mill are being modernized as a new mining level is brought on line. The $40 million investment in mine development and plant modernization positions the Henderson complex as one of the largest, low-cost primary molybdenum producers for the next 15 years. Henderson history The Henderson Mine and Mill facilities are located on the east and west flanks of the Continental Divide about 80 km (50 miles) west of Denver, CO. The underground mine and surface mill sites are linked by 16 km (10 mile) of railroad tunnel and 8 km (5 mile) of surface trackage. The mine, railroad and mill were built between 1968 and 1976 at a cost of $500 million. Each has operated at various levels of production over the past 15 years. The Henderson Mine was originally developed using a highly mechanized, panel caving mining system. Over the past 10 years, mining methods, equipment and railroad operations have been improved to position Henderson as one of the most productive and lowest cost underground mining operations. At the same time, the mill and concentrator facilities were upgraded to reduce costs and improve product quality. During this time, manpower was reduced from 2000 to 560 employees. These 560 people increased productivity to 54 t (60 st) per total manshift. They reduced operating costs by 50%. And they dramatically improved safety performance. However, as the 1990s approached, the modernization of the Henderson mining and milling complex and the development of the new 7700 mining level became the primary goals to guide Henderson into the 21st century.

Jan 1, 1991

By Larry Whittle

Gold milling activities generate waste streams containing dissolved metals and cyanide, among other contaminants, that require some form of treatment prior to discharging to the environment. To date, this treatment has involved the destruction of cyanide through natural degradation, chemical oxidation, or a combination of both followed by the precipitation of metal hydroxides. Although these processes have been proven to be capable of achieving. regulatory levels for metals and cyanide, they often generate significant levels of cyanate and, at times, ammonia, that may be toxic to rainbow trout and thus undesirable for regulatory compliance. Tallon Metal Technologies Inc. (Tallon) has developed Vitrokele™, a chelating resin that has the ability to capture metals (including gold), both total and weak acid dissociable cyanide, as well as thiocyanate from both slurries and solutions. The loaded resin is eluted and returned to the recovery circuit while metals and cyanide are recovered from the eluent stream. This process was demonstrated at pilot scale at B.P. Resources' Hope Brook Gold Mine in Newfoundland, and more recently at Canamax's Bell Creek Mine near Timmins, Ontario. The results from these pilot programs showed metal and cyanide recoveries of 99% or more with the concentration of cyanide and metals in the effluent reduced to levels with minimal or no toxicity to rainbow trout. Furthermore, neither cyanate nor ammonia were generated from the process. The loaded resin was effectively stripped and re-introduced to the recovery circuit; cyanide was captured in the eluent stream and made available for recycling to the mill leaching circuit; and metals were captured for re-use, sale or disposal. This paper summarizes the results obtained from the pilot tests at the Bell Creek and Hope Brook Gold mine sites.

Jan 1, 1992

By John V. Beall

A completed feasibility study executed by an independent agency can benefit a company in two ways. Inside the organization, it verifies the project staffs ideas and their concept of the facility. Outside the company, it can be utilized to obtain equity partners, debt financing, and other forms of credit. It is advisable to bring in a project execution contractor for the feasibility study. A project execution contractor is able to work with engineers to develop the project concept, process flowsheet, and best utilization of the site. By getting an early start on understanding a company's policies and working methods, a project execution contractor saves the company money since it does not have to go through the educational buildup twice. The contractor is a specialist in putting together a bankable document that can be taken to a financing source. It answers all the agency requirements on the first pass. In addition, the contractor can advise an owner on likely financing sources since he works on the worldwide market every day. A less obvious advantage of including the contractor in the study and predevelopment buildup stages is the importance of coordinating finance and technical input. The financing source influences equipment specifications, procurement, logistics, project schedule, cash flow, and liquidity. There are many surprises in store for any manager of a large international project involving worldwide financing and purchasing. The job does not have to be made more difficult by bringing in a contractor after all predevelopment steps are taken. The contractor can still work if the predevelopment steps have been done, even if he does not agree with them. But early contractor involvement is the preferable solution.

Jan 10, 1980

By Ronald I. Fuller

Core Laboratories, a division of Western Atlas International, maintains laboratories in all energy-producing areas of the United States, as well as in many foreign countries. Central to laboratory operations has been the incorporation of computers and computer software. Core has developed a mu1tiuser Laboratory Information Management System (LIMS) , which is currently installed in numerous company sites in the U.S., and is now undergoing installation in Canada. In addition, Core has provided custom soft ware to contract laboratories which Core operates on behalf of mining firms. The software development was done under the direction of the author in Denver, Colorado, and Casper, Wyoming. The intent of this paper is to pass some of the practical experience gained by our efforts on to those who wish to utilize computers more fully in the laboratory setting. The product of analytical laboratories is numbers. Nothing else comes from our work. We deal in information about samples. It is then reasonable to assume that the computer would be central to a laboratory operation. The hard part is to initially define what kind of computer the lab operation needs. The choices today can be very complex, and almost every hardware salesman is full of bad advice. Even the people in your own information services department may hold divided opinions. Since the advent of the personal computer, we have lived with a polarized data processing community. The PC boys consider their machines equal to any challenge, while the "save the mainframe" crowd view the PCs as limited toys that are only good for the things that clutter up a real computer. Management tends to lean toward whatever costs the least.

Jan 1, 1989

By David E. Thompson, Daniel J. Dobbels

INTRODUCTION The planning process for projects requiring construction of tunnels in urban environments can be highly complex and involves interaction with professionals of many disciplines. Typically the initial step in the planning process is to establish basic design criteria for the tunnel or tunnel system consistent with its intended purpose. Such criteria might include acceptable tunnel geometry, minimum and maximum slope or other associated criteria. Ideally, once the basic criteria have been established, the next step in the process might include establishing technically feasible horizontal and vertical alignment and shaft siting alternatives and developing "ball park" construction and operational cost estimates for the alternatives. Comparisons can then be made regarding the relative technical and economic merits of the alternatives and the most favorable alignment(s) are selected for further study or preliminary design. Typically the last and perhaps the most important task that is conducted during the planning stage includes identifying issues and potential problems to be addressed during the design and construction stages of the project. Many issues warrant consideration during the planning phase of a tunneling project. For the purposes of this paper, these issues can be divided into two broad categories: technical and non-technical. Important technical issues include, among others, general design criteria, geotechnical and geoenvironmental issues, and constructibility issues. Important non-technical issues include, among others, right-of-way and easement related considerations, project scheduling constraints, both short and long term environmental impacts and overall cost/benefit aspects of the project. With respect to influence on the planning process, these two groups of issues often cannot be separated completely. For urban tunneling projects, however, it is most often the case that the non-technical

Jan 1, 1991

By Paul C. Jones

Summitville is an old mining district located south of Wolf Creek Pass in the southern San Juan Mountains of Colorado at an elevation higher than 3500 m (11,500 ft). The Summitville mine site is about 40 km (25 miles) southwest of Del Norte. The current mine, developed by Galactic Resources Ltd. and its subsidiaries in the mid-1980s, is on the north facing side of South Mountain. The area is drained by Cropsy Creek to the east and Wightman Fork to the north, both tributaries to the Alamosa River. Mining in the Summitville area began in 1870 when James Wightman discovered placer gold on what is now known as Wightman Fork of the Alamosa River. The first vein-type deposits were located in 1873 on South Mountain near the current Summitville Mine. Mining began in the district in 1875 and continued sporadically through 1942. Major mining episodes occurred from 1875 to 1894 and from 1926 to 1942. Total gold production from the mining district through 1949 totaled 7.5 t (240,000 oz). An additional 7.7 t (249,000 oz) were produced during Galactic's tenure. Natural degradation of the outcropping sulfide-rich veins in the area and the early mining activity, including development of the Reynolds, Dexter and Iowa drainage tunnels in the late 1890s, have polluted the streams draining the area with heavy metals and acidic water. Names of the various tributaries to Wightman Fork, such as Iron, Alum and Bitter Creek, testify to this natural pollution. This degradation has reduced, or killed, aquatic life in several area creeks, including Wightman Fork, for many years before recent mining activity.

Jan 1, 1993

By Virgil R. Huff, Ihor Havryluk

P. T. Pacific Nikkel Indonesia (PTPNI) was incorporated in Jakarta, Indonesia in February, 1969 by a group of Dutch and North American companies. At the same time, a Contract of Work with the Government of the Republic of Indonesia was signed, granting Pacific Nikkel all the necessary licenses and permits to explore and develop all nonradioactive minerals in two separate areas in Irian Jaya, eastern Indonesia. Nickel mineralization occurrences were confirmed by Dutch geologists in the two areas in 1952 and 1955, however, detailed exploration began in June 1969 after the Contract of Work was signed. Since that time, numerous studies and investigations have been conducted to determine the feasibility of producing metallic nickel in Irian Jaya. Four engineering studies, two bulk sample tests, an oceanographic survey, and a preliminary site investigation indicated that construction and operation of a nominal 100 million pounds per year metallic nickel plant on Gag Island were technically feasible. The fourfold increase in the price of oil in late 1973 without a corresponding adjustment in the price of nickel necessitated a reevaluation of the project, the results of which showed that the project required other conditions to be viable. Subsequently, analysis of: the future projected nickel supply-demand and cost-price relationships, the economics of treating a higher grade feed, and participation by the Government of Indonesia, indicate that the project will be viable. Therefore, planning of the Gag Island Nickel Laterite Project is continuing with the objective of commencing production to supply the market in the 1983-1984 time period.

Jan 1, 1979

By Jeffrey J. Schwoebel, Jianliang Li, Daniel J. Brunner

A United Nations (UN) administered degasification technology transfer project, funded by the Global Environmental Fund (GEF) is underway at the Shihao Mine of the Songzao Coal Mining Ad- ministration in the province of Sichuan, Peoples Republic of China. This mine exploits multiple seams at depths ranging from 300 to 600 m below surface. In-seam boreholes and frequently spaced in-mine vertical boreholes, developed from underlying galleries constructed specifically for this purpose, currently degasify the seams in advance of mining at the Shihao Mine. Because of ventilation system constraints and the in-situ gas con- tent, longwall mining of the coals at this mine could not proceed without some form of pre-mining degasification. This paper presents a simulation based degasification plan of long, in-seam horizontal boreholes for the Shihao Mine. Simulations with a coalbed reservoir program assessed time dependent degasification characteristics of both vertical and in-seam horizontal boreholes. The simulations used input data from reservoir and desorption tests conducted at the mine site. The results produced system design nomograms to assist mine engineers in defining the appropriate borehole spacing necessary to degasify the seam in the time available for pre-mining drainage. The predicted effectiveness of the current vertical degasification scheme was compared with that for a horizontal borehole program and served as the basis for the recommended in-seam borehole configuration for the project at the Shihao Mine. The horizontal borehole degasification program requires substantially less gallery and borehole development than the present vertical degasification scheme.

Jan 1, 1997

By Tom B. Corry

INTRODUCTION Located approximately 48 km (30 miles) south of Dallas, Texas, use to be the site of the Superconducting Super Collider. For those of you unfamiliar with the project, this was a multi-billion dollar project taken on by the U.S. Government for the further advancement of technology, medicine, and science. Major components of the project consisted of a Linear Accelerator known as the LINAC; three accelerating rings known as the Low Energy Boosters (LEB), Medium Energy Booster (MEB) and the High Energy Booster (HEB); the East and West Campuses where the Inner Reactor Halls would have been located; and the 87 km (54 mile) main collider tunnel. Unfortunately, this all came to an end on December 6, 1993, with the termination of the project due to the Government's cancellation of funds. This paper will deal with the two of the underground contracts before the termination. These two contracts were the 1122 contract which ran from N25 to N40 and the 1130 contract which ran from N40 to N55. (See figure 1) The 1122 contract was awarded to us in July of 1992 and consisted of the excavation and support of six (6) shaft varying in diameter from 5.5 m (18 feet) to 8 m (26 feet) and ranging from 39.6 m (130 feet) to 61 m (200 feet) deep and the driving of approximately 13,100 m (.43,000 If.) of main collider tunnel. Our second contract, the 1130, was almost identical to our first

Jan 1, 1995

By James J. Olson

INTRODUCTION The need for Government-sponsored research and development to increase excavation rates and lower costs for tunneling and mining operations in a variety of rock types has been emphasized in a wide range of publications from advisory panels, symposiums on rapid excavation, and individuals. In response to the predicted demands for mining and construction-oriented underground excavations for the next two decades (1970-1989), a comprehensive 10-year, $200-million research program in rapid excavation was proposed by the National Academy of Sciences in 1968 (1). Although the large program recommended by the Academy has not been funded, substantial Government-sponsored research in rapid excavation has been conducted during the past several years. This paper reviews some of the significant research accomplishments obtained under a three-year, $6.6-million research program in rock mechanics and rapid excavation sponsored by the Defense Department's Advanced Research Projects Agency (ARPA) and managed by the Bureau of Mines. In addition to the rock mechanics research, five major phases of excavation; systems analysis, geologic prediction, rock disintegration, ground support, and materials handling were represented by the projects funded under the ARPA program. The brief outline below recapitulates the major research areas and some of the projects summarized by this paper: Excavation Process Modeling by Computer Geologic Prediction Geologic Reconnaissance for Site Selection Longhole Probe Drilling for Hazard Detection

Jan 1, 1974

By Ronny J. Sadri

Under contract to the Department of Energy, Fluor Mining & Metals, Inc. and Bonner & Moore Associates developed a group of computer models that can be used to simulate single seam dragline operations. These models have been subsequently modified by Fluor for use in multi-seam dragline mining situations. The single seam model analyzes the digging, spoiling, and walking patterns of draglines to identify possible parameter changes to increase productivity. Parameters such as key-cutting, panel width, digout length, and bench height, etc., are analyzed in this process. The models were tested using data from four operating mines. Field demonstrations were performed to correlate computer optimization results with field data. Productivity was greatly enhanced at one mine site by a change in some of the operating parameters. The multi-seam study has as its objective the development of a broad- based mine planning tool which would be used to identify and quantify the different procedures employed in multi-seam dragline mines to increase their productivity. The major problem identified in multi-seam mining is the sequencing of the different stripping and mining operations. The multi-seam model has the same capabilities as the single seam model. In addition, it models up to four seams with three partings per seam. It allows the operation of several draglines at different levels, and analyzes the effect of ramps, rehandling, and ancillary mining equipment.

Jan 1, 1982

By L. Watkins, M. O’Kane, A. Weir, D. Portefield

BHP Iron Ore initiated a program in January, 1995 at their Mt. Whaleback operation in Newman, Western Australia to develop a decommissioning plan for the waste rock material. The primary research program includes the development of technology for the long term performance of the waste rock dumps with respect to vegetation, slope stability, surface runoff, erosion, and water infiltration. This paper evaluates field performance of cover systems constructed on a horizontal and a sloped waste rock surface. The cover system is constructed using suitable run-of-mine waste material to minimize closure costs. The moisture is subsequently released to the atmosphere as evapotranspiration. Rainfall entering the waste material is buffered due to the presence of the cover material thereby significantly reducing net percolation to the underlying waste rock. The objective is to control acid rock drainage by preventing moisture movement into and through the waste rock material. Two years of field data are presented to illustrate low percolation rates to the underlying waste rock and key performance characteristics of the moisture store and release cover system design. Field data collected to date demonstrates that a moisture store and release cover system constructed with suitable run-of-mine waste material has good potential as a final acid rock drainage control cover system at the Mt. Whaleback site. The performance of the cover system on a sloped surface was significantly altered as compared to placing the cover system on a horizontal surface.

Jan 1, 2000

By G. A. Rowell, T. M. Barczak, J. C. Zelanko

The US Bureau of Mines conducted a multifaceted geomechanics research project at a bump-prone longwall coal mine in eastern Kentucky. This mine presented a unique opportunity to study coal mine bumps because the problem appeared to be confined to areas beneath a sandstone channel of limited areal extent. The Bureau's research plan sought to exploit the uniqueness of the site by monitoring strata behavior and longwall support reactions as the longwall face approached and passed beneath a sandstone channel. The study incorporated static pillar stress and strata deformation measurements, shield support leg pressure measurements and microseismic monitoring, as well as geologic mapping and the collection of observational data. Data collection was underway when a major coal bump occurred on the longwall face at the mine. Pillar behavior (load and deformation), shield loading and microseismic activity were monitored prior to, during and after the bump. Observations in the tailgate indicated that these pillars were failing prior to and following the face bump. Shield load data, evaluated in an effort to identify trends that could be used to forecast coal bumps, appear to provide a measure of the effectiveness of destressing operations conducted on the face (e.g. shot firing). Analyses of microseismic data revealed anomalous values associated with microseismic "energy" prior to the face bump. In addition, microseismic source-location data and underground observations provided some insight as to the sequence of pillar and face bumps.

Jan 1, 1992

In west-central England, 183 m (600 ft) below the Cheshire Plain, lie the evaporate remains of an ancient sea. Stratified into nine beds of salt separated by marl bands, the deposit stretches roughly 21 x 12 km (13 x 7.5 miles) and contains reserves of rock salt estimated as high as 400 Gt (440 billion st). The Winsford Salt Works, one of England's largest underground mines, extracts the Cheshire salt and sells it for use as animal feed, for application in de-icing programs, and as a key ingredient in sodium fertilizer production and a variety of other industrial processes. Because road de-icing is an important market, demand for Winsford's salt varies with the severity of British winters. Design capacity is 2.25 Mt/a (2.5 million/year). However, production peaked at 2 Mt (2.2 million st) in 1987. Over the past five years, annual production has averaged 1.6 Mt (1.7 million st). Run-of-mine salt averages 92.5% NaCl, mixed with about 5% marl. The marl was formed by deposition of a reddish dust blown into the Cheshire basin from deserts in what is now central Europe. Association with the marl adds color to the salt, producing tea-colored crystals that resemble unrefined sugar. Adaptation of coal mining systems Rock salt mining in the Winsford district began at least as early as 1682. Mining at the current site dates from 1844 but was shut down from 1892 to 1928. In the early 1900s, a series of catastrophic collapses and floods plagued and ultimately shut down then-active Cheshire brine-salt producers. Subsequently, Winsford reopened and began adapting mechanized underground coal mining systems to rock salt extraction.

Jan 1, 1992

A group of geologists is located in a remote area of North America, without telephone lines, electricity or even running water. They have spent days accumulating data for a mining company that is eager to receive any information about the dig. But the team does not have access to a wired communications infrastructure. So the geologists must wait until they get to the nearest town to transmit their data. TMI Communications has a mobile satellite communication system that allows geologists in the field to transmit their data from remote locations. The company's satellite is the heart of its North American mobile communications network. This satellite turns all of North America, including Canada, Mexico and the Caribbean into a single digital communications cell. Traditional terrestrial communications systems, such as dedicated phone lines or cellular systems, cannot handle a remote geological exploration camp's extensive communications needs. Cellular technology, where available, has high costs and limited applications. For geologists in the isolated areas of North America, accessible and reliable phone service is vital to success. For those who have established temporary camps, TMI Communications' satellite phone service has improved the speed and accuracy of their communications with home base. This wireless network is suited to meet the needs of existing data applications and the challenges of new ones. It can support any one- or two-way, fixed or mobile data transfer. TMI's network enables geologists to transmit exploration results, spreadsheet information and location co- ordinates to anywhere in the world, at any time. This is important if a team needs to relay vital data back to its headquarters to support immediate decision making on a prospect site or a find.

Jan 1, 1999