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By T. S. Heah, S. T. Bishop

"The Lorraine property is located in the northern Intermontane Belt, north-central British Columbia. The property is underlain by intrusive rocks of the Duckling Creek Syenite Complex, an Early Jurassic, alkaline phase of the Late Triassic-Early Cretaceous Hogem Batholith. Two significant zones of copper-gold mineralization have been explored to date; the Main zone (historical Upper and Lower deposits) and the recently discovered Extension zone. A combined geological resource was estimated in 1975 for the Main zone deposits at 10 million tonnes averaging 0.7% Cu, and from 0.1 g/t Au to 0.34 g/t Au. The Extension zone, still at an exploration stage, is estimated to be considerably smaller than the Main zone.Copper-gold mineralization at Lorraine Mountain exhibits characteristics suggestive of both magmatic and hydrothermal origins, and may be related to orthomagmatic-hydrothermal fluid flow contemporaneous with magmatism and development of migmatitic fabrics. A depth greater than the depth of formation of classical porphyries may explain many of the variations displayed by mineralization at Lorraine. These characteristics distinguish Lorraine from other members of the alkalic suite of porphyry Cu-Au deposits in the Canadian Cordillera.IntroductionThe Lorraine prospect is located in the Omineca Mountains, at the headwaters of Duckling Creek, 56 km northwest of Germansen Landing (Fig. 1). The property is centred at latitude 55°55'N, longitude l25°26'W on NTS mapsheet 93N/14W. The area is typified by mountains of moderate relief, with elevations ranging from 1150 m in the valleys to peaks of 2000 m. Valleys are U-shaped and blanketed by glacial till which give way to steep, talus covered slopes and sharp ridges. Outcrop is generally limited to elevations above 1600 m (Fig. 2)."

Jan 1, 1995

By Jan Yaozhong

The composition and the possible utilization of Ti bearing blast furnace from a titanomagnetite blast furnace smelter were studied. The slag contained about 20% Ti02 and trace Sc. The mineralogical analysis indicated that Ti in the slag is mainly as perovskite. By means of magnetite separation, the Ti containing phase could not be enriched. An effective hydrometallurgical approach was proposed with sulphuric acid leaching. The method proposed for processing the studied slag renders product Ti02 and SC203. Besides the recovery ofTiO2 and SC2O3' the leaching process yields fine grained residues which can used as additives for making cement.

Jan 1, 1996

By M. A. Tomlinson, A. Di Feo, T. C. Cheng

"Goldcorp is evaluating the potential for economic reprocessing of historic tailings at several sites, including the Aunor A facility located in Timmins. The overall project is investigating the ability to recover value, remove sulphide minerals and alternative tailings re-deposition strategies. Desulphurization of tailings will eliminate potential acid generation while improved tailings re-deposition could reduce long-term liabilities and closure costs. Through a task-share project between CanmetMINING and Goldcorp, tailings obtained from Aunor A site have been characterized using mineral association analysis and diagnostic separation techniques. The selected tailing samples contain about 2 g/t of gold. Mineralogical analysis has identified coarse agglomerates bound with gypsum and significant free gold, confirmed by high recoveries in cyanide leach tests. However, despite no evidence of surface passivation on the minerals, conventional flotation techniques were found to be ineffective in concentrating gold or sulphides due to the high fines content and highly agglomerated particles.INTRODUCTION Aunor Mine is one of the historic mines that belongs to Porcupine Gold Mines (PGM) in Timmins, Ontario. PGM has undertaken an extensive mine closure program to remediate the legacy and closed mines with the funding supported by operating mines since 2006. Over the course of 100 years of operation in the Porcupine camp, it is estimated (Stevens et al., 2013) that about 130 million tonnes of tailings have been generated. Aunor Mine produced 2.5 million troy ounces of gold between 1940 and 1984, while processing over 7.6 million tons of ore. The original gold grade of Aunor Mine ores was about 10 g/t. With 95% gold recovery at the time, an estimate of 0.5 g/t of gold remains in the Aunor Mine tailings. Aunor Mine has two tailings impoundment areas: designated as Aunor A and Aunor B. The two sites are similar in size, about 7 hectares each. The amount of tailings in the Aunor A site alone is about 3.2 million tonnes. In 2017, bulk tailings were sampled from five designated locations in Aunor A. They were characterized using mineral association analysis and diagnostic separation techniques. The bulk tailings samples contained about 10% total sulphur, 10% iron, 2% arsenic and 2 g/t of gold. The prime objective of this collaborative work between CanmetMINING and Goldcorp is to facilitate the timely development and deployment of innovative tailings reprocessing solutions, specifically in the areas of desulphurization, and recovery of metals. This work targeted specific tailings of interest to Goldcorp which goals are to improve its environmental footprint and to reduce long-term liability. Thus, it is imperative to look for innovative reprocessing options that can overcome not only technological challenges but also achieve economic benefits to offset the costs associated with reprocessing the tailings. Moreover, the greater goal is to demonstrate and deploy tailings reprocessing solutions to solve one of the industry’s most difficult challenges for a sustainable mining industry in Canada."

Jan 1, 2019

By James R. Norris, Thomas A. Conto, Gary R. Walter

For at least five decades, a plume containing acidic metal-bearing water has been moving through the shallow alluvial aquifer along Pinal Creek in the Globe-Miami area. Two chemical facies of water are distinguished in the alluvial aquifer: (1) a metal-rich acidic plume with gram per liter concentrations of metals (primarily iron) and pH values between 3 and 5 and (2) neutralized water with a pH greater than 5, low concentrations of metals, and high concentrations of sulfate and manganese. Historically, the acid plume has moved through the aquifer at an average velocity of 0.6 m/day, ten times slower than the average pore velocity of groundwater in the aquifer calculated using the Darcy equation. The rate of migration of the metal-rich plume is retarded by pH-dependent chemical reactions between acid water and the aquifer matrix. As acid water is neutralized by reaction with calcite, rising pH conditions in- crease the oxidation rate of iron and decrease its solubility resulting in the precipitation of ferric hydroxides. The formation of ferric hydroxides is a proton releasing reaction which main- tains acidic conditions. The acidit of the plume and the neutralization capacity of tKe aquifer are best assessed in terms of the iron content of the water and not the hydrogen ion activity computed from pH measurements. The parameters controlling plume migration are: (1) the calcite content of the aquifer (2) the iron acidity of plume water, and (3) the rates of acid neutralization and ferrous iron oxidation. A numerical solute transport and reaction model based on the concept of iron acidity effectively simulates the historical development of acidic conditions, predicts the behavior of the plume, and was used as a management tool to identify the most efficient and cost effective remedial strategy.

Jan 1, 1991

By F. Calizaya, S. Bhattacharyya

"INTRODUCTION Mechanized underground mines often suffer from noise overexposure. Noise levels are usually above the Permissible Exposure Limit (PEL) where underground fans are used. Sound levels in active workings can reach 121 dB(A), especially when fans are not equipped with silencers. Use of silencers seldom ensure PEL for various reasons. Overexposure of noise induces permanent hearing loss among mine workers. Recent field studies by a NIOSH-funded research project at six coal and non-coal mines revalidated the findings. The University of Utah has undertaken laboratory studies to reduce fan noise at the source. A new silencer prototype with varying noise dampening material has been designed and tested. The silencer and an associated extension which can be repacked with different dampening materials were used in various configurations. Attempts were made to simulate field conditions where installations are quick and not perfect. The test results are presented here. NOISE IN UNDERGROUND MINES Noise induced hearing loss (NIHL) is a chronic problem in the mining industry. In spite of regulations being in place and elaborate hearing protection programs under way, hearing loss is prevalent among the mine workers (Bise, 2001). All production and support machinery in mining generate loud noise often beyond the approved exposure level. Researchers in the U.S. have identified auxiliary fans as one of the major sources of noise that can create noise exposure levels up to 121 dB(A), which is one of the highest in the mining operation (Bauer, 2006). Studies have demonstrated substantial reduction of noise level by using silencers. Adequate fan selection and proper utilization of silencers in auxiliary fans have great potential of abating the problem. In hard rock mines, auxiliary fans are used in blower configuration to ventilate development headings and large production stopes, and also to ventilate underground shops, crushers, conveyor transfer points, etc. Typical duct diameters in hard rock mines vary from 0.91 m to 1.21 m. Silencers are often omitted for cost reduction. In coal mines auxiliary fans are used in exhaust configuration with rigid ducts 0.61- 0.76 m in diameter (Hagood, 1982 and Moreby, 2009) to ventilate working faces in gate-roads and main entry developments. Sometimes, stone dusters are added at the discharge end to dust the roof, ribs and floor. AUXILIARY FANS AND SILENCERS Auxiliary fans are relatively smaller in size than the main fans and often have high rotational speeds (1800 -3000 rpm). Fans are selected based on pressure-quantity requirements and space restrictions only. Noise emissions are rarely considered during the selection stage. Installation of fans, ducts and other accessories is mainly based on best practices, which often do not include noise control. As a result, the operation of an auxiliary or local ventilation system normally produces excessive noise."

Jan 1, 2018

By M. A. Trevits

Methane gas is an ever-present problem facing the underground coal mining industry. Mine operators are mandated by law to maintain safe concentrations of methane gas within the mine environment. Ventilation is used by all mine operators to reduce gas concentrations. When gas emissions are such that ventilation alone cannot control the gas, methane drainage methods must be applied. In the 1970's, there was a concern that unprecedented gas emissions would be experienced as mine operators began new developments in the deep and gassy Blue Creek and Pocahontas No. 3 Coalbeds. Such concern was well founded as significant gas volumes are being emitted as these mining operations mature. In 1971, the O.S. Bureau of Mines began to tabulate and track the change in mine emissions. These data were extracted from the underground coal mine quarterly air quality-quantity inspections performed by the Mine Safety and Health Administration. At that time, approximately 6,560 Mm Id (231.7 MMcfd) of gas were emitted from 430 underground coal mines. It was determined however, that the mines emitting less than 2,832 m Id (100 Mcfd) contributed only 2.1 percent of the total daily gas flow. In 1988, underground coal mines emitted 8350 Mm Id (294.9 MMcfd) from 487 mines. This report evaluates the changing nature of U.S. mine gas emissions over the last 18 years.

Jan 1, 1993

By Motyka J, Adamczyk AF, Witczak S

A case study of migration of a paper factory fluid wastes, on the distance of 5 km from an underground disposal site to an ore mine is presented. The ore mine in question, situated in SW Poland is pumping 3.5 m3/s (ca 300 000 m3/day) of groundwater, producing a cone of depression about 150 m deep and several kilometers wide. The migration of wastes (pollutant) occurs within the carbonate karstic aquifer of Triassic age. The aquifer is about 100m thick and is characterized by the coefficient of hydraulic conductivity equal to 8 m/day on the average. The results of systematic measurements carried out for 13 years enabled to estimate the mean breakthrough curve of the pollutant. On this basis and taking into account the coefficient of hydraulic conductivity as well as the mean hydraulic gradient between the disposal site and the ore mine, the migration parameters of the polluting material, i.e. the real flow velocity, the effective porosity and the longitudinal disper- sivity have been calculated. As the measurements considered a long migration distance of the pollutant, the obtained hydrodynamic dispersion constant (dispersivity), in the authors opinion, is reliable enough to be applied for regional groundwater calculations, regardless of the "scale effect".

Jan 1, 1988

By T. J. O’Neil, S. J. Kirk

In 1978, a multidisciplinary team from the University of Arizona, the Mines Project Group, conducted a study to examine reclamation alternatives for a proposed open-pit copper mine. The cost of a waste dumping plan designed by a mining consulting firm was determined as well as the cost of dumping configuration prepared by the Mines Project Group. The latter dumps were designed to be more socially acceptable and aesthetically pleasing, in addition to serving more creative end land uses than the dumps designed by the mining consultant. One dump configuration designed by the interdisciplinary team was the least expensive plan of all the alternatives considered.

Jan 1, 1984

By T Smith, J Hatley

With the increased focus on the need for more uranium mines, this paper presents the design process currently underway for the development of the Millennium deposit in northern Saskatchewan, Canada. This deposit, located 630 - 750 m below surface, will be accessed by two shafts and will be mined by blasthole stoping methods at less than 500 t/d. Mining grade will approximate two per cent U3O8 and mine life is expected to be six to seven years. The project is a joint venture between Cameco, AREVA and JCU. This paper discusses in detail methods used to predict worker radiation exposures, the methods used to monitor the work environment and procedures unique to the uranium industry necessary to minimise worker radiation exposures.

Jan 1, 2008

By Jeane Hull

Jan 1, 2009

By Mark A. White

Arch Mineral has developed several computer programs that aid the surface mine planning function. These programs are utilized to perform long term projections for various area or semi-area stripping operations. The program generated reports include yardage, tonnage, quality and ratio information for the user-specified time periods. The projections are used to anticipate the annual budget, to compare alternative mine plans and to analyze acquisition candidates. The programs are user friendly, fast and accurate. Geological Grid File Two data files must be set-up and used in conjunction with the mine planning programs. These are a geological data file and a general input file.

Jan 1, 1984

By R. Benito

This paper describes the development of a life-of-mine schedule (LOM) for one of the world's largest known sedimentary copper-cobalt districts located in the Katanga Province, Democratic Republic of Congo (DRC). A particular feature of the Tenke Fungurume LOM schedule is the considerable number of pits/phases for scheduling, each competing to provide the best ore available to a capacity-constrained process facility. This paper discusses the LOM scheduling objectives and constraints, data preprocessing steps such as ore binning, block aggregation and clustering analysis as a scheduling aid, the mine scheduling approach and results and conclusions. Mining Engineering, 2011, Vol. 63, No. 8, pp. 39-47. Official publication of the Society for Mining, Metallurgy and Exploration, Inc.

Jan 1, 2011

This paper examines some of the important aspects of mineral taxation policies and practices, with reference to the mining tax regimes of selected Pacific Rim countries (see Tables 1 and 2). The following subjects are addressed:what is æmineral taxationÆ?, basis for mineral taxation, types of mineral taxes, objectives of the mineral taxation regime, best practices, and mineral royalties. Many countries, in some cases with the encouragement and assistance of international funding agencies, are actively assessing the international competitiveness of their mining tax regimes with a view to attracting investment. However, these countries recognise that the mining tax regime is not the only consideration that is taken into account by prospective investors. The countryÆs geological prospectivity, physical infrastructure, labour force, political risk, and regulatory system are also important factors in the investment decision making process. Although it is probably true that an attractive mining tax regime will not necessarily attract mineral investment, there is a real possibility that an unattractive regime can drive away investment. For example, Hugo Dummett, general manager for discovery at BHP, hinted recently that BHP could cease exploration in Russia in the absence of positive tax changes. Dummett is reported as saying that if taxes æend up being as onerous as they are now, we really have to rethink why we are hereÆ (Mining Journal, London, November 27, 1998).

Jan 1, 1999

By E. P. Youngman

The basic mining law of French Morocco is the Edict of 1914, "Danir of Jamary 19, 1914, for the Regulation of Mineral Prospecting and Exploitation in the Zone of the French Protectorate of the Cherifien Empire," which, as the preamble states, was promulgated at the instance of the Director General of Public Works, in consideration of the fact that mines constitute one of the sources of wealth of the Empire. According to a consular report, dated May 18, 1923, by Bradford, men- tioned above, the mining industry of that country, aside from the exploitation of the extensive phosphate deposits, can scarcely be said to exist, but the potential field for mining is promising. However, no large-scale exploitation of the mineral wealth of French Morocco can be hoped for until there is complete pacification of large areas that are still in an unsubdued state or until adequate transportation facilities, scientific prospecting, and large investments of cap- ital are assured. An edict in 1920 (Dahir of January 27, 1920) modified the law mentioned above by declaring the prospecting for and the exploitation of phosphates to be exclusively reserved to the Government. The Dahir o. August 7, 1920, announced the creation of the Cherifien Phosphate Office (Office. Cherifien des Phosphates), a State monopoly charged with the exploration, management, and exploitation of the phosphates of Morocco.

May 1, 1930

By Drew A. Meyer

Magnetic metals are the granddaddy of products which may be recovered from municipal waste. Aside from hand-picking of newsprint and corrugated boxes, magnetic metals are usually the first items a resource recovery facility considers extracting from the solid waste stream. Magnetic metals from incinerator residues and from municipally mandated source segregation programs were first used in significant quantities by the Copper Industry. The ability of the Copper Industry to consume metals from the municipal solid waste stream raised everyone's hopes that there would be more markets for municipal scrap when more of it became available. Somehow something has gone wrong. It is widely acclaimed that scrap is an environmentally sound and economical source of iron. It is greatly in demand for Its contained energy. The prices that the steel industry has been willing to pay for the scrap during the past year are all the proof anyone should need that scrap Is desirable and sought after. But the very fact that I'm speaking today on the markets for magnetic metals recovered from municipal waste indicates that something Is wrong. Clearly the problem is not that we do not need the scrap. The problem is we have not produced the kind of scrap that consumers are willing to buy - either through ignorance of what the consumers wanted or through a conviction that ferrous scrap is so obviously a good thing somebody will surely want it no matter what. Dr. Harvey Alter of the National Center for Resource Recovery has said "You can't sell garbage". In a sense that is only partly true. It really should be "You can't sell garbage for very long". The Steel Companies, in an effort to prove that steel is an environmentally desirable packaging medium, have bought some scrap that can only be described as garbage. They are to be commended for doing so. The fault lies not with the Steel Company for taking and paying for "garbage" but with the producer of that poorly prepared scrap. Far every instance where the steel industry has purchased the often undesirable product from resource recovery facility there are several magnetic installations sitting Idle because someone forgot the most essential part of producing the magnetic product - selling it to someone.

Jan 1, 1975

By Jean J. Tancous

Chromium recovery from wet-blue offal trimmings and shavings can be done with substantial chemical cost gains by incineration at 600° C for 5 hr. Pretreating the offal with 0.5 M Na2C03 and air-drying prior to incineration produce Cr04 .By simply incinerating the offal, without pretreatment, an ash containing water insoluble Cr203 was produced. The Cr203 in the ash was purified by leaching with water. Chromium and crude protein were efficiently extracted from offal using 5 pct Na103, 5 pct H2S04, and 3 pct NaCl at 40° C. This procedure was effective but expensive. Satisfactory leather as to odor, appearance and shrinkage temperature was made from chromium recovered from wet-blue offal by incineration and by extraction. Chromium conservation is possible by recycling chromium liquors and by precipitating chromium from spent tanning liquors prior to combining these liquors with other tannery wastes. Combining chromium liquors with other wastes introduces contaminants that make chromium recovery and reuse difficult. Leaching sludges with H2SO4 produced marginal chemical cost gains. Leather tanned with these solutions had satisfactory shrinkage temperature but the sludge odors and iron contamination were objectionable.

Jan 1, 1979

"INTRODUCTIONThe information compiled in this volume initially formed the response by the Generic Mineral Technology Center for -Respirable Dust (GTCRD) to a review of its research and technology transfer programs performed in 1990 by the Advisory Committee on Mining and Mineral Resources Research. This review for each mineral technology research center is accomplished, as required of the Bureau of Mines by the House/Senate Joint Conference Committee, through site visitation to the research institutions of the GTCRD and an in-depth questionnaire. The information provided by that questionnaire becomes an important factor in their recommendations concerning future directions of the program.The site visitations took place during January and February 1991 at the Milton S. Hershey Medical Center~ The Pennsylvania State University, West Virginia University, University of Minnesota, and Michigan Technological University, in addition to an in-mine visit conducted at the Loveridge Mine in West Virginia. The questionnaire was prepared and made available to the Advisory Committee and the Research Council for their review at the GTCRD annual project review meeting in Hershey, Pennsylvania, in April 1991.The comprehensive nature of the questionnaire and the scope of the information contained therein make it an excellent retrospective of the Center. Having a clear vision of where the Center has been and knowing where it is now helps to guide it into the future. It is believed that such a detailed view of the Center's facilities and research program will be of value to Center personnel and Advisory Committee members. Each aspect of the questionnaire was examined, answered in detail and documented thoroughly. With the completed questionnaire as a guide, this review of the Center's activities provides an update to Respirable Dust Center Research Program Review 1988, published in 1989 as the seventh of the Generic Mineral Technology Center for Respirable Dust volumes. As does that volume, this review presents the complete General Mineral Technology Center questionnaire, with the GTCRD's expanded responses and supporting documentation appended. An examination of the research program, Center personnel currently active on GMTC projects, the number of graduate degrees granted with GMTC supports GMTC publications, the degree of individual interaction, technology transfer activities, the reference center, GMTC equipment and facilities, and envisioned plans for future research directions provides updated information in these areas. In addition, this year, information has been included to demonstrate the interaction between the Center's goals and its research projects, with thorough consideration of actual research needs as specified by the National Academy of Sciences. This volume serves as a review of the years 1989 through 1990, the sixth and seventh years of the Center's operation."

Jan 1, 1990

By Reynold N. Hoover, Davis S. Shatzer

The Bureau of Alcohol, Tobacco and Firearms (ATF) is responsible for the regulation and enforcement of the explosives laws codified in the Organized Crime Control Act of 1970, Title XI. To meet its responsibilities ATF has special agents, inspectors and specialists who regularly interact with the explosives industry. However, with just over 2,000 special agents and 800 inspectors and specialists, it is difficult to visit the almost 10,000 explosives licensees and permittees in the United States.

Jan 1, 1995

By Henrique Silva Furtado

This paper presents the results obtained on the exchange of an original old blow charge model for a new up-to-date state of art global model, employing optimization techniques and process modelling, and, the results obtained in terms of fluxes consumption reduction and the introduction of user friendly tools and practices.

Aug 17, 2017

By E. J. Marcotte

"INTRODUCTIONThe Upper Canada Mine is located at Dobie, approximately ten miles east of Kirkland Lake, Ontario.The mill contains Upper Canada's cyanide circuit and Upper Beaver's flotation circuit. The combined capacity is 590 tons per day consisting of 415 t.p.d. of Upper Canada gold ore and 175 t.p.d. of Upper Beaver copper-gold ore.The Upper Beaver ore is trucked five miles to the Upper Canada mine site.Crushing:The crushing circuit consists of primary, secondary and tertiary crushing employing one C .A. C. 15 in. x 24 in. Superior jaw crusher, one 4 ft. x 8 ft. Tyler-Niagara double deck screen, one 3 ft. Symons standard cone crusher and one 3 ft. Symons shorthead cone crusher.The -2 in. product from the jaw crusher is fed to the double deck screen. The+ 5/ 8 in. passes over the top deck to the 3 ft. standard cone crusher; the+ 3/ 16 in. material passes over the lower deck to the shorthead cone crusher. The - 3 / 16 in. material pas sing through the lower deck of screens is the product to the mill.The screens used prior to the installation of rubber screen cloths were: one 4 ft. x 4 ft. section with 3/ 4 in. square openings and one 4 ft. x 4 ft. section with 5/ 8 in. square openings on the top deck; two 4 ft. x 4 ft. sections with openings of 3/16 in. x 4 1/2 in. slot on the lower deck. The fine screens were positioned so that the 4 1/ 2 in. slots were parallel to the flow of feed.The crushing circuit is operated on a three shift per day basis by one operator per shift."

Jan 1, 1968