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By K. Wangerud, B. S. Caruso

A water balance model with deterministic and stochastic components was developed and used for the Gilt Edge Mine Superfund Site, South Dakota, to evaluate risks of contaminated runoff discharging to surface waters based on assumed water treatment plant (WTP) rates for different remedial alternatives. The objectives of the modeling were to use a stochastic approach for analysis of precipitation based on historic records, and for probabilistic estimation of annual and monthly runoff from primary disturbed/mining activity areas that currently requires, or will need, treatment at the WTP, water storage and changes in a major pit, and risk of contaminated water bypass of the WTP to a downstream drainage. Subareas/source areas generating contaminated runoff requiring treatment were delineated. A simple water balance model was used based on precipitation inputs and evapotranspiration and groundwater losses. Annual and monthly precipitation records for Lead, South Dakota were used to estimate precipitation at the mine site. A lognormal distribution was estimated for monthly precipitation. The stochastic software package/Excel add-in “@Risk” was used to generate random monthly precipitation values using a Monte Carlo method based on the distributions. The average annual and monthly distribution of pan and lake evaporation, and groundwater losses were also estimated for the site. Stochastic outputs from the model for the end of each month and year included contaminated runoff requiring treatment, water storage in mine pits and the risk of WTP bypass given different assumed WTP rates. The probability of the time required to dewater the pits was also modeled.

Jan 1, 2002

By G. W. Adams

Foreword While the literature on radium is voluminous, there is no single publication available from Canadian sources which attempts to cover at all fully the world radium industry. The comparatively recent developments in the Wilberforce area, and the consequent arousal of public interest in radium, seemed to call for the publication of such a paper which would be intelligible to the layman. To satisfy this apparent need, the writers submit this paper which contains material derived from various sources, and for which the writers make no claim of originality. Direct references are made throughout the paper to sources of information.

Jan 1, 1931

By Max W. Ball

THE world's largest known oil deposit lies in northern Alberta. In fact, according to government estimates, the famous so-called 'tar sands' of the Athabaska region contain several times as much oil as all the other proved reserves of the world. S. C. Ells, of the Department of Mines and Resources, who has been the Dominion Government's authority on the oil sands since 1913, has estimated the minimum content of the deposits at 100 billion barrels(!). C. P. Bowie, of the U.S. Bureau of Mines, has published an estimate of 250 billion barrels(2). ?In comparison, the latest authoritative estimate of the proved oil-field reserves of the world is less than 35 billion barrels(3). Out of this tremendous total, perhaps 500 million barrels are commercially available at present-day costs and prices; the remainder must be considered a latent reserve to be used when development costs are materially lower and petroleum prices materially higher than they now are. Mean-while, the 500-million-barrel portion presently available contains more oil than has been found in all the rest of Canada, and constitutes one of Canada's great mineral resources. Although these deposits have been known to white men since 1788, when Peter Pond, the explorer, found the Indians stewing the oil out of the sand and mixing it with spruce pitch to caulk their canoes, they are only now coming into commercial production. The purpose of the present paper is to describe the deposits, their oil content, their present development, and the possibilities that seem to lie immediately ahead. For the sake of completeness and clarity, the writer has not hesitated to use or to paraphrase material that he has previously published elsewhere in discussing various aspects of the oil sands.

Jan 1, 1941

By Harry W. Campbell

A Bureau of Mines investigation identified no mineral deposits in the Lost Creek RARE II area. Sand and gravel has been mined from alluvial flood plain deposits just outside the RARE II boundary. An oil and gas lease application which includes the eastern portion of the RARE II area is pending. Abundant basalt in the area can be crushed and used as aggregate; but it could not compete with similar deposits in more favorable locations, or with cheaper substitutes such as volcanic cinders or sand and gravel which are available outside the study area closer to major markets. No indication of coal or geothermal energy resources was found. INTRODUCTION Location and Access The Lost Creek RARE II area encompasses 8,300 acres (3,400 ha) of Lassen National Forest in north-central California, about 20 mi (30 km) north of Lassen Peak. The closest city is Redding, California, 50 air mi (80 km) southwest. Peripheral access is provided by State Highway 89 passing near the western RARE II boundary (fig. 1). The Pacific Crest Trail traverses the western margin of Hat Creek Rim adjacent to the eastern boundary of the area.

Jan 1, 1983

By Cam Thomas

The initial application for reflectorless laser technology was for profiling rock faces to determine front row burden and improve flyrock control and airblast. Over the past fifteen years a number of laser systems have been developed for general ground modeling purposes and GPS offsets, but these advances have yet to gain common acceptance in construction, mining and quarry blasting. This paper will outline a number of applications for reflectorless laser technology, including the latest method for rock face profiling, mapping, and 3-D modeling to calculate available and excavated rock volumes. Drilling deviation measurements will be presented in conjunction with rock face profiling to demonstrate how this information can be used to improve blast results. In complicated excavations, the actual quantity of rock excavated for payment purposes and the amount of overbreak can be very controversial. Procedures to calculate these volumes using laser technology will be outlined and comparisons will be made between these results and traditional techniques.

Jan 1, 2003

By James L. Ash

This report contains the results of a technical and economic evaluation of conceptual systems for the underground mining, rubblization, and in situ retorting of deep oil shale deposits. Study efforts were first directed towards evaluation of the applicable geology, associated minerals, rock mechanics, in situ retorting, access mining, ventilation, rubblization, safety, and environmental impact factors. Conceptual systems were synthesized and then evaluated against these factors from both a technical and limited economic viewpoint. The results of these evaluations were then analyzed and, based upon this analysis, the following two systems were selected for further study: System II: Room and Pillar-Vertical Drill and Blast System IV: Tunnel Boring-Horizontal Ring Drill and Blast Due to the large number of variables to be considered, a computer program was developed and utilized to provide data for the cost trade-off studies and economic analysis. Results of the early computer runs indicated the value of the tool available? in the computer program and led to an extension in the contract to determine the sensitivity of the systems to several of the more apparent significant variables. These results in turn led to a refinement in the design assumptions and a better understanding of the technical and economic options available to an owner-operator of a Vertical Modified In Situ Shale Oil Extraction System. This report is submitted in fulfillment of the requirements of Contract Number 50241073 by Fenix & Scisson, Inc. to the Denver Mining Research Center, United States Department of the Interior, Bureau of Mines. Work was completed as of November, 1976.

Jan 1, 1976

By Steve Kral

MINExpo INTERNATIONL 2000 was a good place for companies to introduce new products, technologies and services to the mining industry. Caterpillar took that a step further. The company hosted a one-day preview of its mining products at its Tinaja Hills Training and Demonstration Center near Tucson, AZ. About 30 members of the trade press spent the day at Tinaja Hills before heading on to Las Vegas for MINExpo INTERNATIONAL 2000. Dozens of Caterpillar professionals provided the editors with a first-hand look at Caterpillar’s mining trucks, loaders, excavators, road graders, water trucks and engines. In addition, these Cat experts explained the intricacies of each piece of equipment, the latest technology that led their improvement and their value to the company’s mining customers.

Jan 1, 2000

By Richard G. Stearns

Extensive thick lignite apparently lies within 250 feet of the land surface in Dyer, Lake, Lauderdale, Obion and Tipton counties. Information on geology, land use, soils, groundwater and instability is compiled, along with a bibliography. A test and monitoring site was investigated at Fort Pillow Prison in Lauderdale County. Analyses were made of lignite, overburden, associated water and leachate. Lignite has high BTU (about 7800) and low sulfur (1.1% avg.). A year or more of data are presented on rainfall, water levels, and chemistry of surface water, groundwater, leachate and water from test pits. Main potential environmental problems are quality of surface water, and possibly shallow groundwater. The main aquifer of the region will likely be un-affected by mining. Low transmissibility of shallow aquifers will minimize lowering water levels of wells. Soil reclamation and conservation should be readily accomplished, Dangerous earthquakes have a low probability and mines are not significantly more hazardous than steep bluffs.

Jan 1, 1981

A composite iron ore-reductant pellet is a mixture of fine iron ore and fines of coal/char/coke, bonded at essentially room temperature with sufficient green strength for subsequent handling. In ironmaking, these pellets offer the advantage of fast reduction, utilisation of fines, non-coking coal and coke breeze. The composite pellet-based alternative ironmaking processes constitute a promising route for ironmaking in future. The present paper is a brief review of kinetics and mechanism of reduction of iron oxides into iron and other associated reactions, when these pellets are heated to high temperature. It would draw significantly from investigations conducted by the author and his co-workers.

Jan 1, 1999

Even though the economy of the United States remains in recession ? or not, depending on which economist you listen to ? muicipalities still need improved transportation, water and wastewater transit systems. And they are willing to spend the necessary funds on those systems, provided they are affordable, environ-mentally friendly and sustainable. From June 20-23, professionals in the tunneling and underground construction industry from around the world gathered in Portland, OR to learn new ways of providing those systems using the latest technology available. The North American Tunneling (NAT) conference attracted 803 attendees and 108 exhibiting suppliers of equipment and services.

Jan 1, 2010

By Steve Wilson, Bern Klein, Jeff Drozdiak, Stefan Nadolski, Andrew Bamber

"In the adaptation of high pressure grinding rolls (HPGRs) to hard-rock mining applications, circuit development has mainly focused on placing HPGRs in the role of tertiary crusher in the preparation of ball mill feed. In order to take advantage of the potential energy benefits associated with HPGR and stirred mill grinding technologies, work was done to investigate the potential of and resultant energy benefits of placing the HPGR in series with a high speed stirred mill in replacement of the conventional cone crusher / ball mill arrangement. The proposed circuit was designed to operate with two stages of HPGR grinding followed by high speed stirred milling.Using a pilot-scale HPGR unit inline with a 20 liter stirred mill, the design criteria, circuit arrangement and consequent comminution energy requirements for a circuit processing copper sulphide ore from Teck Resources’s Mesaba Copper project were determined. These results were then compared to two other circuits, an HPGR / ball mill circuit and a conventional crusher / ball mill circuit processing the same ore.The testwork indicated at a proof-of-concept level that the HPGR / stirred mill circuit could potentially be appropriate for this duty and further work on the concept is merited. While the results indicate that the HPGR component of the circuit was more energy efficient than conventional cone crushing, the energy efficiency of the stirred mill was found to be lower than that of a comparable ball mill undertaking the same duty. However, increased energy efficiency of the stirred mill portion of the circuit is possible with further optimization and further work on the concept is indicated."

Jan 1, 2010

By Martin Herrenknecht

After the successful breakthrough at the end of 2006 of both TBMs into the multifunctional site Faido (MFS), in the middle of 2007 the two tunnel boring machines resumed the 12 km long section between Faido and Sedrun. In the roughly a 10 month interval both approximately 465 m long tunnel boring machines were partly dismantled, pushed through the 2.5 km long MFS, rebuilt for the new larger diameter of 9.5 m and reassembled to be ready for operation. In the rebuilding phase, improvements were made to the equipment, especially as a result of experience gained from the previous 14 km long drive in the section Bodio and taking into account the latest information regarding the upcoming 14 km section Faido. Both TBM drives are currently in the rock formations of the Lucomagno gneiss, which stretch over a section of 3.5 km from the MFS Faido to the predicted Piora Syncline. This section is divided into two fold axes of the Chièra Synform, where the Lucomagno gneiss pass from a sub-horizontal into vertical bedding. The drives, with current rock overburdens exceeding 1,500 m and, as known from the excavation phase of the MFS, in part highly disturbed rock formations, are characterized by the locally intense rock squeezing conditions with large convergences in the vicinity of the driving TBM as well as backwards due to the interaction of the two drives. High expenditure for the support measures, reduced driving performances together with extensive extra work associated with deadlines and increased costs are the result. In the paper the previous experience with the TBM drives in the section Faido and the challenges still awaiting us are presented and discussed.

By Hugh S. Spence

IN MAY, 1930, G. LaBine and E. C. St. Paul, prospect¬ing round the southeastern shore of Great Bear Lake, in the North West Territories of Canada, discovered pitchblende at what is now LaBine Point. At the same time, they also found native silver in a small sheared break on an island lying off the point. Late in 1930, samples of the pitchblende were sent to the Mines Branch, at Ottawa. The material consisted of several fair-sized slabs of botryoidal pitchblende banded with a brownish quartz. A small amount of chalcopyrite was visible as small particles and fine veinlets, and the pieces were rather heavily stained a yellowish-green by secondary copper-uranium salts. Analyses were run in the Mines Branch Ore Dressing Laboratories on two samples, and small-scale concentration tests were made on one of them. The results of this work were published in a Memorandum Series report (No. 48) of the Mines Branch, in March, 1931.

Jan 1, 1932

The wealth of a nation can be measured many ways, but one of the most important measures is its natural resources, particularly minerals. Minerals provide the foundation upon which economic prosperity and defense preparedness rest. Assessing our energy and mineral resources and assuring their development is in the best interests of all our people continues to be an important national goal. Since its founding in 1910, the U.S. Bureau of Mines has established itself as the world's premier minerals information and research agency. Its authoritative, comprehensive data and pioneering research have contributed significantly to a strong U.S. mineral position in the world.

Jan 1, 1990

This report presents the results of a study of mill tailings disposal practices and potential tailings dam stability problems. Recognizing the long period of time that would be required to develop the technology and practices necessary to significantly improve refuse disposal safety, the Bureau initiated this research effort as a first step in that development. Volume 1 includes a summary of conclusions and recommendations resulting from the overall research effort; discussions of disposal systems and methods, geology, seismicity, hydrology, and materials characteristics; evaluations of investigational techniques; discussions of usable interim generalized investigational, analytical and inspection procedures; discussion of general principles and presentation of a tailings technology manual outline; and discussion of needed future research am recommended programs.

Jan 1, 1974

By Howard E. Parkinson

In 1969, new coal mine health and safety legislation was enacted in the United States. As a result of this legislation, the Department of Interior, Bureau of Mines has carried out communications research aimed at developing whole mine communications for increased safety and efficient operation. The research has advanced and many promising results are now being demonstrated to the mining industry. However, there remains a challenge to further improve wireless communications within the mine workings and through the overburden above the workings. The objectives for future research and development will be discussed, together with the physical and operational constraints that new mine communication systems must face.

Jan 1, 1973

"At a current mining rate of 3,750 tons per day, La Mine Doyon is currently the largest gold mine in Canada. La Mine Doyon is an open pit gold mine located in the Abitibi area of Northwestern Quebec. The project is a joint venture between Soquem, a Quebec Crown Corporation in the resource development field and Lac Minerals Ltd., a publicly-held, resource development company. Lac Minerals is the managing company and operator of the project.Doyon went into production in 1980 on a very limited basis at 600 tons/day, and has seen a step wise increase to the current rate of 3,750 tons/day. Initially, all the ore was processed at Noranda Mines, Horne Division as flux for the copper smelter. The East Malartic Mill in Malartic was then upgraded and began processing Doyon ore. The third step in the progressive increase of throughput was the commissioning of the Doyon mill in November of 1982. Doyon ore is currently being processed at all three locations.During 1983, an exploration ramp was driven to explore the ore below the ultimate pit depth. Current plans indicate the sinking of a shaft and the commencement of underground mining during the next 2 or 3 years.Since its humble beginning, La Mine Doyon has always been a success; ore reserves have been extended to the east and the west and will soon be confirmed at depth, the mining and processing rates have been increased 6 fold, and the recovery has been increased from a designed recovery of 85% to over 95%. The intent of this paper is to trace the history and reasons for these rather dramatic improvements."

Jan 1, 1984

By Peter Barker, Terry Jones

"The Kelsey Centrifugal Jig (KCJ) utilizes the application of centrifugal force (and the resultant enhanced gravitational field) to conventional jigging technology principles to successfully and efficiently process materials where the valuable constituent particulates are very fine and/or where there is a small specific gravity differential between these and the gangue minerals.The KCJ is applicable to a broad range of fine mineral recovery duties, with current installations in the mineral sands, tin, tantalum, gold and nickel industries. Other areas of application are being developed with mineral commodities including tungsten, base metals, iron ore, chromite and apatite/feldspar.Information on the principles of operation of the KCJ, typical performance figures in a number of application areas, comparison to centrifugal concentrators, key elements for a successful KCJ operation and recent developments with the KCJ are presented in this paper to demonstrate the capabilities of the KCJ.INTRODUCTIONAfter a number of years of development by inventor Chris Kelsey, the first commercial KCJ unit was installed at the Renison Bell tin mine in Tasmania, Australia, in 1992. The subsequent decade saw the installation of further KCJ units in applications including tin, tantalum and mineral sands.Development and improvement in KCJ hardware continued and culminated in the introduction of the high-capacity Model J1800 KCJ and standard features such as an automatic screen cleaning system. This opened up further markets and resulted in Model J1800 KCJ installations in the gold and nickel industries, as well as further KCJ installations in the mineral sands and tin industries. In recent years, work has continued on application of the KCJ to many other duties in industries including tungsten, base metals, iron ore, chromite, apatite/feldspar, etc."

Jan 1, 2007

By J. J. S. Sebastian

The process development described in this report was carried out at the Morgantown Station of the U. S. Bureau of Mines in cooperation with West Virginia University. An experimental laboratory-scale pilot unit to gasify coal dust in entrainment was constructed on the Campus of the University in Morgantown. The enormously accelerated demand for liquid and gaseous fuels and utilization of our immense coal resources require that a low-cost process be developed for the gasification of a wide variety of coals. Such a process would be a major factor in lowering the cost of synthetic liquid fuels. None of the proc3sses developed in Germany prior to and during World War II, such as the Winkler process, the H. Koppers dust gasification process, the Wintershall-Schmalfoldt process, etc., meet all the requirements for a low-cost process under American conditions. Nor has any other process designed and experimentally operated at atmospheric pressure during the post-war period in this country appeared to fulfill all of the necessary conditions for a low-cost process.

Jan 1, 1950

By E. I. Robinsky

"This paper describes a new, proven approach for tailing disposal. Not only is the disclosed system less damaging to the environment, it is also less costly to operate, to close down and maintain in perpetuity. The basic concept is to discharge thickened tailing from one permanent location.This creates a conical or hill-like deposit which:(1) requires lower perimeter dykes for equivalent storage capacity;(2) eliminates decant towers and decant lines;(3) requires no steep dams built of tailing;(4) is stable:(5) requires only a small pond outside the deposit;(6) decreases pollution of the surrounding environment by water seepage and deflation; and(7) simplifies abandonment and ""closing-down"" operations.The approach is made possible by the fact that, at a sufficiently high ratio of solids to water, tailing material can be made to accumulate at slopes of 5 or 6 per cent -- considerably steeper than possible by traditional methods using low solids-to-water ratios. To achieve the necessary solids-water ratio (35 to 60 per cent), it may be necessary to install a thickener. It is expected, however, that at many concentrators it may be possible to discharqe relatively clear plant water through a line separate from the tailing line, thus reducing the load on the thickener."

Jan 1, 1976