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By Oren C. Baptist

Umiat field contains the largest accumulation of oil discovered so far in Naval Petroleum Reserve No. 4 in Arctic Alaska. The Umiat anticline was tested with 11 wells; 6 produced oil in varying quantities. Behavior of the wells during testing was unpredictable. For example, one well was abandoned as a dry hole after all tests failed to recover any oil, yet an offset well, only 200 feet from the dry hole, produced 400 barrels of oil a day. The main oil reservoirs are less than 1,000 feet deep and are in the permanently frozen zone (permafrost). Reservoir pressures are low, and most primary production will be by expansion of gas-in-solution in the oil. Because of the unusual reservoir conditions and the difficulties encountered in drilling and completing the wells, the Department of the Navy asked the Federal Bureau of Mines to make laboratory studies of the reservoir sand to determine the cause of well plugging and to provide laboratory information, to be used as an aid in estimating oil recovery from frozen reservoir rocks under solution-gas expansion from low-saturation pressure conditions.

Jan 1, 1960

By P. Croney

Environmental monitoring requires major effort and expense but management of data receives less attention. A modem database system can manage hydrochemistry, water levels, meteorology, geology and downhole geophysics data and is flexible to allow the storage of ad hoc data. Reports can be customized by the user and derived data generated from input values. The production of high quality maps with contours and hydrochemical diagrams is an essential part of the reporting process. These maps integrate directly with the current site survey information. These facilities are best provided by storing the data in an industry standard database such as Oracle or Access to which customized AutoCAD and Microsoft Office routines make direct SQL calls.

Jan 1, 1997

By Stephen F. Munsell

The development of transportation systems for mined materials has historically been characterized by steadily increasing sizes in basic hauling units. This is especially true for open pit mines for which success is dependent upon the economical transportation of vast quantities of material. The depletion of high grade ore reserves has mandated a tremendous increase in the size and complexity of the ore haulage systems necessary for open pit mines, These increased demands were served by rail haulage systems in the early large open pit copper mines while later developed properties opted for the flexibility and lower initial costs of truck haulage. Now, we find the trucks being displaced as large overland belt conveyors tackle the problem of handling these ever larger quantities of low-grade ores with accompanying overburden ratios that can run as high as 10:1 or even 15:1. The basic development of large conveyors with shiftable sections and modular belts has generally taken place overseas, during the last few decades. The coal fields of central Europe proved an ideal testing ground for conveyor innovation because the low density and natural friability of the material created an ideal medium for transporting by belt conveyor. Now these proven ideas are being considered for and implemented into both the soft and hard rock mining industries of the United States.

Jan 1, 1978

By C Berglin

Is the Northern Territory different? Certainly it is more remote, has less people and relies more heavily on two or three industries for its survival. On the other hand, its mining industry is governed by Acts not dissimilar to those of the major States - a Mining Act provides the basis for acquisition of tenure, a Mine Management Act provides regulatory control, a Mineral Royally Act collects revenue in return for the right to utilise the land's bounties, an Environmental Assessment Act provides the public face to rehabilitation and environmental safety, and the Aboriginal Land Rights (NT) Act purports to give development criteria for inalienable land use. With the exception of the latter, at least until the advent of Mabo, all these are simply variations on a theme, and are common to most States. This paper will show how the Department of Mines and Energy works in relation to the Northern Territory mining industry.

Jan 1, 1994

By John W. Bell

A FEW years ago the writer had the privilege of examining a piece of apparatus in the Forest Products Laboratory of McGill University which engaged his attention. The Forest Products Laboratory has an excellent installation of wood-grinding machinery, and the officials in charge were naturally interested in acquiring means for estimating the fineness of various wood grinds. The problem was referred to Dr. O. Maass ( l ). Dr. Maass designed a piece of equipment to measure the surface of a wood grind and derived an equation applicable in calculating its value, as follows : After inspecting this apparatus, the writer was disposed to believe that, with some modifications, Dr. Maass' ingenious idea might be utilized to measure the surface of mineral powders. Obviously, some difficulty would be found in maintaining an even suspension of mineral particles of high specific gravity compared to that of wood pulp. The writer will not bore the reader with a description of the various machines built and tried out. Some of these were satisfactory enough to obtain some valuable information, and to bring to light a difficulty which threatened to bring the investigation to an abrupt ending. For the mineral quartz, it was found that Kin the formula above stated was not a constant.

Jan 1, 1944

By D. L. Whiting

Dump leaching and ,in-situ solution mining have received considerable attention during the past few years due to their apparent economic viability and minimal environmental impact. Solution mining actually dates back to the 17th century when leaching of copper ore was first reported. However-, modern day leaching didn't begin on a wide scale until the mid-1900's. In-situ mining for copper, nickel, salts, and oil shale is currently looking more attractive as the technology advances. Presently, about 15 percent of the copper production in the United States is from leaching operations at approximately 14 active sites, the largest of which are the waste dumps near the Bingham Copper Mine, Utah. To establish a common background, the discussion is centered around state-of-the-art conditions. For dump leaching, complications inherent to the physical conditions and chemical reactions such as channeling, porosity and permeability, sorption, air flow, rock alteration and pH control are discussed. Emphasis is made on those conditions which render solution recovery rates and solution mineral concentrations unpredictable. By illustrating typical and actual field conditions, the generally accepted flow theories for both dump leaching and in-situ solution mining, including rubblization, are presented. For in-situ mining, hydrogeologic techniques such as geophysical well logging, aquifer testing and digital computer modeling are also discussed. The importance of artificial fracturing and well stimulating to solution injection and recovery is made with regard to project development. Finally, the subject of water pollution control techniques and the potential impact of the

Jan 1, 1977

By A Gibbs

Culture and leadership go hand in hand, especially when it comes to investing in safety. But the reality is that most safety leaders haven’t been taught the fundamental soft skills needed to lead effectively. In fact, only one in four safety leaders demonstrate effective skills and behaviours. Furthermore, when compared to its peers in other high-risk industries, our research indicates mining has the most room for improvement when it comes to effective safety leadership. In this presentation safety culture, climate and leadership will be outlined. Additionally, research data collected from our clients, across a variety of industries, will be shared to inspire reflection on the value of safety leadership. Finally, strategies to empower leaders and increase safety leadership behaviours will be described.

May 5, 2022

By L. Alan Weakly

The Powder River Basin of northeastern Wyoming and southcentral Montana contains the largest strip minable reserve of compliance coal (0.27 kg or 0.6 or less Ibs of sulfur per million Btu) in the United States. In mining parlance, it is the mother lode. Wyoming's portion of the Basin is called the Southern Powder River Basin (SPRB). It has been the nation's top coal producer for the past nine years. And based on 1997 production statistics and estimated strippable compliance coal reserves, Wyoming should remain the nation's top producer for the next 51 plus years. In August 1994, ME featured 10 articles that covered all aspects of coal production in the SPRB. In this issue, five authors update the 1994 articles and provide a pre- diction of what the Basin will look like at the turn of the century. In addition to this article, the titles and authors of the other five articles include: ? "Geology of Wyoming's Powder River Basin coal field," by Gary B. Glass and Robert M. Lyman. ? "Coal quality challenges in the Powder River Basin," by Sharon Roness, Richard A. Turpin and Robert A. Young. ? "Markets for Southern Powder River Basin coal," by , Patti J. Best and Patrick W. Wright. ? "Evolution of mining equipment in the Powder River Basin," by Kenneth R. Miller and James L. Long. ? "Hauling coal into the 21st century," by Dave Willis and Will Cunningham.

Jan 1, 1998

By C. G. Anderson

Industrially proven and applied nitrogen species catalyzed (i.e. NSC) acidic pressure leaching has been utilized to treat a number of ores, concentrates and recycled materials. This versatile technology offers many advantages including low temperatures, low pressures, low capital costs, low operating costs, faster throughput and less costly materials of construction than conventional pressure oxidation. This paper will elucidate the application of this technology for production of gold, silver, palladium, rhodium, zinc, germanium, gallium, cobalt, copper and nickel. Recycled material applications will also be elucidated. In addition, details of an application for treatment of a refractory chalcopyrite copper and gold bearing ore will be presented and pertinent economics discussed.

Jan 1, 2004

By Paulo Masiero

Sintered titanium carbide has been extensively used since the early 1980s for demanding wear-resistant applications and, in particular, in environments characterized by high temperature and oxidation. Thanks to its physical characteristics, especially its low density, titanium carbide (TiC) has been successfully applied in the manufacture of cassette guide rollers for hot steel rolling. However, the peculiar characteristics of the sintered Ti carbides make it difficult their redressing and hence this has always represented the limit for a more extensive application. Very often iron based alloys are preferred even if, in general, they are less cost effective just because they are easier to be redressed by turning. The availability of a simple, compact, fully automatic and reasonably priced CNC machine; specialized in the grinding of guide rollers and able to operate accurately and efficiently -both in contour and in plunge- can definitively solve TiC’s redressing problems and render its use even more widespread and attractive.

Oct 30, 2017

By J. M. King

A crucial step in the acquisition by one company of the assets of another, the acquisition of the stock of another company, or the merger of two com-ponies, is the legal due diligence which needs to be performed in order for the acquirer to ascertain or confirm the obligations, liabilities and exposures to risk that are being assumed along with the assets or corporate stock being acquired. Where the obligations, liabilities, or exposures to risk arise from existing contracts, or from pending lawsuits, administrative proceedings, or threats of these actions, those matters are relatively straightforward to discover by careful review of the files of the party whose assets or stock is being acquired. However, where a company is engaged in ongoing mining or processing operations and has operated or owned mining proper-. ties, there are many sources of liability and exposure to risk which could have major adverse economic consequences to the acquiring party and which are not revealed, or at least are not clearly delineated, by the records of the company whose stock or assets are being acquired.

Jan 1, 1990

By G. E. Willey

F OR many years, only one grade of structural steel has been used in volume in Canada. Its characteristics have not been altered appreciably and its long use speaks well for its performance. This standard grade of structural steel may be bought and specified as C.S.A. G40.4 steel or the American equivalent, A.S.T.M. A7. The principal limitations and requirements of this specification are shown in Table I. Within the last five years there has been a growing awareness among the steel producers and steel fabricators that economic forces are at work which make desirable the availability of new and better grades of structural steel. Competition from other materials has increased. The use of concrete bridges and pre-stressed concrete beams is a prime example. New sources of steel from outside the country have become a threat to the Canadian industry and its high cost-price structure. The need for improved properties in the steel, to make possible technologic

Jan 1, 1962

By Tomek Ulatowski

INTRODUCTION In 1974, Industrial Miners Mexico, S.A. (IMMSA), agent for the borrowers, was the largest privately-held mining, smelting, and refining company in Mexico (accounting for 32% of Mexico's nonferrous metal and coal production in 1974), the fourth largest company in terms of sales, and the second most profitable company in Mexico, excluding government wholly-owned and operated industries. The company was engaged in the mining, smelting and refining of coal, copper, fluorite, gold, lead, silver, zinc and related by-products for domestic consumption and export. A combination of favorable factors led IMMSA to propose an investment plan amounting to US$286 million for 1974 through 1978, of which US$150 million was to be financed. These factors included: Substantial profits in 1973 and 1974 Positive near-term outlook for metal prices Success of the reinvestment program in increasing productivity Substantial additions to proved reserves during 1973-1974 and Fiscal incentives provided by the Mexican government to stimulate investment in the mining industry. The primary purpose of the investment program was to construct a new electrolytic zinc refinery and to expand and modernize many of the company's existing mining and refining facilities. THE BORROWER Company History Compania Miners Mexico, S.A. was incorporated in the city of Monterrey in 1918 as a wholly-owned subsidery of ASARCO Inc. (formerly American Smelting and Refining Company, New York) for the purpose of mining and processing non-ferrous metals and related products. In compliance with the Government's Mexicanization program, ASARCO Inc. divested itself of 51% of its equity in Compania Miners Asarco, S.A. on June 30, 1965. Subsequently, ownership in the divested share was apportioned as follows: 15% ownership in Compania Miners Asarco, S.A. to a group of private investors, and 36% in trust for subsequent public sale. The company's name was changed to Asarco Mexicana, S.A. in 1965. Mexican ownership in Asarco Mexicans, S.A. was increased to 51% in 1967, following the purchase of the 36% share ownership held in trust, and then to 66% in 1974 when ASARCO Inc. divested itself of an additional 15% of its holdings in Asarco Mexicans, S.A. Following its 1974 divestiture of 15% of Asarco Mexicans, S.A., ASARCO Inc's ownership in Asarco Mexicana, S.A. was reduced to 34%. In 1974, the company changed its name for the second time to Industrial Miners Mexico, S.A. (IMMSA). Fiscal Agreement IMMSA entered into a fiscal agreement with the Mexican government in 1969. The agreement, which was renewed in 1974, provided for 100% of the production and export tax corresponding to the federal government with a minimum of 50% of the amount refunded to be reinvested in fixed assets. Further, the agreement permitted the company to

Jan 1, 1985

Jan 1, 1902

By H. Brindel

The paper point out the importance of a maintenance program at Toquepala, as to the effect that any changes in the above may have on the program and organization. The Southern Peru Copper Corporation carry out a training program in operation with a appropiate peruvian staff, as it has been established the basics for a sound, preventative maintenance and repair organization. In consecuence, this company decided to expand a two -fold program of training and maintenance so that the Peruvian personnel will not only be an aid to the Company but a national as set to Perú as well.

Aug 20, 1963

By I. Duckworth

P.T. Freeport Indonesia operates a mining complex located in the highlands of Papua, Indonesia. This district consists of both underground and surface operations. The East Ertsberg Skarn System (EESS) is one of the major orebodies in this district. Subsurface caving of the EESS has been carried out in a systematic series of mining lifts dating back almost 30 years. Present production is from the third lift (Deep Ore Zone), which is scheduled to peak at 80,000 mtpd during 2009, with this rate sustained through 2015. The orebody is proven below the existing caving level, with the next vertical block called the Deep Mill Level Zone (DMLZ). This paper presents an overview of the DMLZ Mine based on recent feasibility level study. The mine is being designed for a peak production rate of 29.2 million mtpy, with 1,803 total ore draw points spread over a panel caving footprint of about 1.3km by 375m. The present reserves for this mine total 501 million tonnes. Located 1,400-1,800m below the original surface, the DMLZ will be one of the deepest caving operations in the world. Production is scheduled to commence in 2015. Discussion is provided on most design aspects including; caving methodology and layouts, geotechnical predictions and risks, ore handling systems, ventilation design and associated infrastructure, high-lift pumping system, cost estimation and expenditure scheduling.

Jan 1, 2010

By Paul L. Michael

This report presents a discussion of perforance parameters for electronic or active hearing protectors that will meet the needs of underground coal miners. This information is incorporated into a proposed set of specifications that can be used to judge the suitability of a particular electronic hearing protector for the coal mine application. Acoustic and electrical tests were performed on a developmental model of an electronic hearing protector built by the U. S. Bureau of Mines. This model showed only a slight reduction in speech intelligibility which was traced to poorly matched components and in particular to the transducers. Tests of alternative components showed the Knowles BL-1671 microphone to be suitable for this application because of its performance and extremely small size. The Roan-well H-143/AIC earphone was found to have a good frequency response but has the disadvantage of being rather bulky which causes a slight degradation of a low frequency attenuation of the hearing protector. A satisfactory installation of these components in a hearing protector muff was demonstrated and tested. Results of tests of several methods of controlling the sound level under the hearing protector muff showed that a simple diode clipper circuit can be used with only a negligible loss in speech intelligibility for normal-hearing listeners. A commercially available active hearing protector, the British-built ACOS A-9000/2 was examined. This hearing protector provides sound level limiting through a saturating amplifier. Preliminary tests have shown that the performance characteristics of this commercial unit meet many of the proposed specifications so further testing and evaluation should be performed to determine its suitability for use 1n underground coal mines. The recommended test of intelligibility for electronic hearing protectors and other communication systems as used in a coal mine setting is the Modified Rhyme Test (MRT) developed by House et al. in 1965. The suitability and method of administering this test are discussed.

Jan 1, 1976

By T. J. Haddon

For the mining industry in general and gold mining in particular the past few years have been difficult. Economic conditions coupled with growing regulatory restrictions have led to increasingly important reasons for managing assets wisely. From a public company perspective this makes sense because it ultimately provides for an increase in shareholder wealth and that's what we're in business to do. Regardless of whether a company is public or not, assets must be managed effectively to remain a player in today's competitive environment. So, as the CEO of a gold mining company, how do we manage our assets to ensure that we are satisfying our obligations to our customer --the Amax: Gold shareholder? Let me tell you. As I said earlier, the gold industry has been under siege. We have just completed our third year of average prices below $400 per ounce. When you add finding and/ or acquisition costs and development costs to operating costs, there isn't much of a profit margin left. What this environment provides, however, is opportunities for growth. In the gold business, you either grow or you die. Today, most North American gold producers have at most a 10 year mine life. We are all scrambling to add reserves so we don't become extinct. As prices remain low, opportunities for increasing diminishing reserves abound. This is the time for the opportunistic company to take advantages of market conditions and that's precisely what we, at Amax: Gold, have done!

Jan 1, 1992

By Bruce K. Hebblewhite

This paper provides an overview of the international ?state of the art? with respect to underground coal mining methods used in seams of thickness greater than 4.5 m, through a review of a selection of high performing thick seam mining operations around the world?both Single Pass Longwall (SPL) and Longwall Top Coal Caving (LTCC). The paper discusses the recent operational experiences from these selected faces, together with the ground control issues faced, and identifies some of the major, inherent geotechnical factors that can influence the mining method selection, design criteria, and ultimate performance, from both an operational and safety perspective. It is clear that both of these methods are developing quickly? not only from an operational and equipment perspective, but also from the understanding of critical geotechnical criteria. There is an increasing role for both methods in thick seam environments, although the higher SPL faces will only be successful in the near to mid-term under benign geotechnical environments. Regardless of the method, a thorough understanding of the critical geotechnical factors is a key to successful implementation of either method.

Jan 1, 2013

By Circe Verba, Scott Montross, Jon Yang

This work is a first-order study to assess the suitability of an organic acid lixiviant to extract rare earth elements (REE) from coal preparation fines refuse sourced from a Pennsylvania mine with a total REE of ~ 300 ppm. The extraction of REE using an organic acid, in this case 0.1Mcitric acid and 0.5Mtrisodium citrate solution, is compared against 0.5M(NH4)2SO4, 1MHCl, 1.2MH2SO4, and 0.5Methylenediaminetetraacetic acid (EDTA). Ashing the coal waste material prior to leaching tests with the citrate solution nominally improved REE extraction. Buffered citrate solution recovered 7% of the total REE in the as-received Isabella Fines as compared to 11% in ashed samples, whereas (NH4)2SO4 extracted 5–6%, respectively. EDTA recovered up to 33%of the total REE, most likely due to the higher coordination chelate bond. Mineral acids, however, outperformed the organic acids on ashed material (16–52%REE recovery), suggesting that organic acids may not be a suitable competitive option for REE extraction from these types of feedstocks.

Jun 15, 2021