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By T. G. Joseph, M. J. Bolster

ABSTRACT This paper explores passive seismic measurement as an alternative, nonintrusive approach to conducting annual brake testing on surface mine sites. Dictated by the test site location, this evaluation adhered to the brake testing procedure as per British Columbia occupational health and safety regulations. Results showed excellent correlation to those reported via conventional practice: Comparing stopping distance, time, and velocity for the proposed instantaneous passive seismic versus conventional approaches, less than a 0.5% variance was evident. A viable alternative, the passive seismic approach, allowed an entire fleet of trucks to be sequentially evaluated for annual brake testing without disrupting operations by installing mechanical testing equipment.

Jan 1, 2012

By H. D. Lelono, M. Walden, G. Johnson

3D modelling can be used throughout the mine lifecycle and has proven to be a powerful tool for consultants and mining companies. One of the most significant benefits of 3D models is their ability to enhance collaboration, communication, and understanding between the mine owner, design engineers, and other relevant stakeholders that have a shared interest in responsible mining and site management. Tailings and mine waste management is an interdisciplinary effort that requires effective coordination and communication between a wide range of consultants, operators, and stakeholders alike. The increased emphasis on Environmental, Social, and Corporate Governance (ESG) highlights the importance for mine operators to engage and communicate with all parties involved in the planning, permitting, operation, and closure of mine sites. 3D models are valuable tools that can be used for development of geotechnical conceptual models, allowing for improved design and monitoring of Tailings Storage Facilities (TSFs). A clear conceptual understanding of a TSFs subsurface geology and foundation characterization is essential for proper tailings management, design, and planning. Visualization with 3D modelling can simplify the interpretation of the, oftentimes intricate, mine sight subsurface settings and allows for quick and effective geotechnical conceptualization. 3D models can be used to identify data gaps, optimize field investigations, and streamline the development of numerical stability or groundwater models. They can help communicate the complex nature of subsurface and TSF interactions in a clear, concise, and accurate manner to both technical and nontechnical stakeholders. This paper discusses some of the benefits of 3D modelling in relation to geotechnical analysis for tailings management and provides methodologies for how to improve upon some methodologies that are considered industry standards.

Feb 1, 2023

By E. A. Barrett

The U.S. Bureau of Mines (USBM) conducted experiments to determine if training using a latent-image, three-dimensional (3-D) slide simulation exercise improved miners' ability to recognize roof and rib hazards. The effectiveness of this innovative type of classroom training was investigated by measuring workers' performance on a hazard recognition task. The study was unique in that hazard recognition skills were assessed in the workplace using actual coal mine roof and rib hazards. Results showed that training with a latent-image, 3-D slide simulation exercise significantly improved each subject's performance on the in-mine hazard recognition task. Further, the USBM researchers concluded that transfer of learning from the classroom to the workplace occurred.

Jan 1, 2010

By J. F. Brune

This paper analyzes the explosion hazard resulting from the formation of methane-air mixtures in the mined-out gobs of underground longwall coal mines. Although direct examinations of the gob atmosphere are difficult due to the inaccessibility of these gobs, evidence from methane drainage practices and investigations of numerous mine explosions suggests that explosive methane zones can form within longwall gobs. Explosions and fires resulting from these methane accumulations have led to severe and fatal injuries to the miners. Most recently, this was demonstrated in the explosion of the Upper Big Branch Mine in West Virginia, where 29 miners lost their lives.The paper also reviews current research on numerical modeling of gas flows in longwall gobs and outlines how targeted injection of nitrogen into gobs can effectively reduce the volume of such explosive methane zones. The paper concludes that comprehensive monitoring of gas compositions, along the accessible fringes of the gobs along with inertization, improved ventilation schemes and further research are necessary to control this explosion hazard and make mining operations safe.

Jan 1, 2013

By Wllliam D. Davis

C OMMERCIAL production of oil in northeastern Oklahoma began in 1897 and in the next two decades this area became one of the greatest oil districts of the time. Its importance is now secondary, but thousands of wells in this area have produced uninterruptedly for more than thirty years. They are now classified as stripper wells. By means of what is known as water flooding their L. production can be considerably in- creased. This practice consists in injecting water under pressure into the sand surrounding an oil well, thus displacing the oil in the pores of the sand and forcing it into the oil well.

Jan 1, 1940

By AIME AIME

T HE Executive Board of the American Engineering Council held its fourth meeting at St. Louis on the first anniversary of the organizing conference which met in Washington on June 3,1920. Representatives of a number of the leading engineering organizations in the vicinity of St. Louis were present by invitation. The members of the Executive Board were guests of the Associated Engineering Societies of St. Louis. They were given a delightful ride about the city and were entertained at the Glen Echo Country Club at dinner. The special committee that had been appointed to draft resolutions to Mr. Hoover submitted the following, which were adopted : WHEREAS, our President, Herbert Hoover, has been appointed Secretary of Commerce in the Cabinet of the President of the United States, and WHEREAS, in consequence of his acceptance of this high public office, he has deemed it necessary to tender his resignation as President of The Federated American Engineering Societies.

Jan 1, 1921

By Brenton Cook, Daniel Mageau, Larry Applegate, Aaron McCain

"Ground freezing was successfully used to create an impermeable barrier wall along 3,000 feet of the downtown Seattle waterfront as part of the Seattle Seawall Replacement Project. This $360 million re-development involved removing the original 1930-era seawall and replacing it with a new, seismically resistant concrete wall supported on fill soil improved by jet-grout. The replacement wall was one of the largest construction projects in the state of Washington at the time. Ground freezing is typically used as both a structural shoring wall and groundwater cutoff. However, at this project it was used primarily as a cutoff wall to stop groundwater seepage into the 16-foot deep excavation from the landside areas.The project was divided into ten boxes (sections), each typically 200 to 600 feet in length. Only a few boxes were under construction at one time to reduce the impact on tourist-dependent local businesses. Soil conditions in the freeze zone consisted of sand, gravel and silt fill with abundant wood and debris. Tidally influenced groundwater, much of it contaminated, was difficult and expensive to control using wells during initial stages of construction. For all subsequent stages, a frozen soil wall extending to about 35 feet in depth was used to stop groundwater seepage into the excavation. An additional benefit of ground freezing included elimination of potential settlement beneath nearby buildings, utilities, and the Alaskan Way Viaduct that would likely have occurred with the use of conventional dewatering wells. The frozen soil wall crossed more than 130 buried utility locations (including water, sewer, storm, electrical, fiber optic, phone, gas, steam) with no damage. The frozen soil wall was very successful and limited groundwater influx from the landside to the seawall excavation to a negligible amount so that pumping, storage and treatment of contaminated groundwater was essentially eliminated."

Jan 1, 2016

By W. R. Hardwick

This Information Circular describes copper mining and concentrating methods, practices, and costs at the Silver Bell Unit of American Smelting and Refining Co., Pima County, Ariz. It is one of a series being prepared by the Bureau of Mines on mining methods, practices, and costs in various mining districts of the United States. The Silver Bell mining district, one of the older districts in Arizona, is in the western part of the Silver Bell Mountains in Pima County, about 40 miles west of Tucson and about 20 miles southwest of Red Rock, a station on the main line railroad of the Southern Pacific Co. The Oxide and the El Tiro open-pit mines of the American Smelting and Refining Co. are in the district (fig. 1. The principal ore deposits are in T. 12S., R.8E., Gila and Salt River base line, at an altitude of about 3,000 feet. The present town of Silver Bell, established in 1952, is reached by a paved highway, the Avra Valley road, that turns west from Highway 84 at Plata siding near Rillito and extends westward 25 miles to the townsite (fig. 2). The present town is about 5 miles southeast of the old town of Silver Bell that flourished from 1900 to 1930.

Jan 1, 1963

By W. R. Hardwick

This Information Circular describes copper mining and concentrating methods, practices, and costs at the Silver Bell Unit of American Smelting and Refining Co., Pima County, Ariz. It is one of a series being prepared by the Bureau of Mines on mining methods, practices, and costs in various mining districts of the United States. The Silver Bell mining district, one of the older districts in Arizona, is in the western part of the Silver Bell Mountains in Pima County, about 40 miles west of Tucson and about 20 miles southwest of Red Rock, a station on the main line railroad of the Southern Pacific Co. The Oxide and the El Tiro open-pit mines of the American Smelting and Refining Co. are in the district (fig. 1. The principal ore deposits are in T. 12S., R.8E., Gila and Salt River base line, at an altitude of about 3,000 feet. The present town of Silver Bell, established in 1952, is reached by a paved highway, the Avra Valley road, that turns west from Highway 84 at Plata siding near Rillito and extends westward 25 miles to the townsite (fig. 2). The present town is about 5 miles southeast of the old town of Silver Bell that flourished from 1900 to 1930.

Jan 1, 1963

By A. K. Croteau

"At Craigmont Mines Limited, Merritt, B.C., the mining practice of trackless sub-level caving was started in the latter part of 1966. This type of mining was new to the mine personnel and the mining industry of Canada as a whole. Sub-level caving has presented many old and a number of new problems in maintaining the equipment used in this method. This paper will deal with some of these problems as they affect this particular mining operation. It will be impossible to review all phases of the equipment, but an attempt will be made to cover the most pertinent aspects in maintaining the drilling, mucking and hauling, and auxiliary equipment."

Jan 1, 1970

Largely inherited from the past and from strictly internal laboratory use, the certification of reference material using round-robin assaying is often insufficient for the use made today for external assay laboratory control by client parties. Certification often needs to be revisited on the basis of existing round-robin data, especially to derive reproducibility parameters to the end of establishing probabilistic performance gates for operational error detection on a batch per batch basis (ie batch-ærejectionÆ). The most common difficulty arises when only a few certification samples have been analysed in one single batch by each laboratory, so that the round-robin data do not contain the full variability that needs to be quantified. Existing certification data sets from properly submitted round-robin samples were studied using analysis of variance to derive a remedial method, leading to the proposal of default correction factors to restore full variability estimates when no other avenue is available.

Jan 1, 2008

By T. Patching

"THE FOLLOWING notes on coal mining in the Edmonton city area are based, in the main, on scattered reports and accounts as little coal mining has been done in this area for about 20 years and few people are left who were involved in what was at one time an important industry of northern Alberta. Although coal mining is not likely to be permitted in the city area itself in the future, a record of this work is warranted to indicate the ·conditions and problems that may be encountered if underground mining again is proposed in the district in the same geological formations and in similar strata. Coal mining in the Edmonton area developed with the influx of settlers in the latter part of the nineteenth century and the first part of the present century. Probably local coal was used by the Fort's blacksmith as early as 1841, and the early settlers probably were 'gopherholing' into the outcrops along the river banks by the 1870s. The first report of commercial coal mining was in 1880 when a contract was let by the Hudson's Bay Company for the provision of 300 tons. As the population in the city and northern parts of the province grew, many new mines were opened along the river and in the district, and coal was even shipped by barge to points in Saskatchewan(1 ,2) By 1909 the Department of Public Works reported that 'Edmonton stands as the second largest domestic coal producing centre in the province'. It continued to hold this position until 1942. From about 1912 to 1951 annual production from mines in the city and surrounding district ranged between 0.38 and 0.65 million tons, depending on weather, wars and strikes. Production began to decline in 1951 because of the increasing availability and consumption of natural gas which was piped into the city and then provided to other towns and rural areas in the northern part of the province. Taylor noted that between 1880 and March 1970, when the last mine within the city area closed, the total of mines and prospects within the Edmonton city area rose to 153. Most of them were small; not more than 20 produced more than a quarter of a million tonnes during their entire life, and only three produced a million tonnes or more. As described by Taylor ""within the city district workings extend discontinuously from the apex of a narrow triangle near Groat Bridge to the base of the triangle in the Clover Bar area"". The larger mines were in this latter area. Approximate locations of the old mine workings in the city are shown in Taylor's atlas. A number of other coal mines were worked in the Rabbit Hill, Big Island, St. Albert, Namao, Cardiff and Morinville districts around the city."

Jan 1, 1985

By S. McPherson, M. Chalkley, R. Ellenwood, W. Nicot

"The Moa JV was formed in December 1994 as a 50/50 joint venture between Sherritt Inc. and General Nickel Company S.A. of Cuba. The joint venture consists of the mine and Pedro Sotto Alba processing plant in Moa, Cuba and the Corefco refinery in Fort Saskatchewan, Alberta, Canada. Throughout its now nearly 23-year history, the Moa Joint Venture has faced a number of global, operational and process challenges. Global challenges have included high input costs such as for fuel oil and sulphur, as well as low nickel prices. Operational and process challenges have included increasing ore haulage distances, decreasing ore Ni + Co grades, and increasing ore impurity contents. For example, increases in impurities such as Mg and SiO2 in the ore result in increasing acid demand in leaching and decreasing solids content of preheated leach feed slurry, respectively. In spite of these challenges, the mixed sulphide production capacity from the Moa Joint Venture has increased from 12,500 to 37,000 t/y Ni + Co since 1994 by judiciously targeting expansion projects and by continuously performing process and operational improvements.INTRODUCTION The Pedro Sotto Alba high pressure acid leach (HPAL) plant at Moa Bay, Cuba has a long history (Maslenitzkiy, 1969; Chalkley, 1996; Carlson, 1960; Roy, 1961; Carlson 1961). The plant was constructed by Moa Bay Mining Company and started up in late 1959 after several years of process development by Freeport Nickel Company, including operation of a 10 t/d plant in Hoskins Mound, Texas and a 50 t/d plant in Port Nickel, Louisiana (Southwick, 2004), as well as development work by Chemical Construction Company (Chemico) to precipitate metal sulphides (Roy, 1955a; Roy, 1955b). The Moa plant had an original reserve of 50,000,000 t of ore, graded at 1.35 wt% Ni, 0.146 wt% Co, 3.70 wt% Si, 1.00 wt% Mg and 4.5 wt% Al. At original design rates of 2,000 kt/y of ore, the design capacity of the plant was around 25,000 t/y Ni + Co as a mixed sulphide product, which would be shipped to the Port Nickel Refinery in Louisiana for processing. In 1960, the plant changed ownership and was restarted in 1961 under Cuban management. Between 1961 and 1989, the plant was also supported by involvement from the former USSR, supplying spare parts and consumables. In 1994, Sherritt Inc. partnered with the General Nickel Co. S.A. of Cuba and formed the Moa Joint Venture. This joint venture includes the mine and Pedro Sotto Alba HPAL processing plant in Cuba and the Corefco refinery in Fort Saskatchewan, Alberta, Canada. Under this partnership, ore is processed in Cuba to produce a nominally 55 wt% Ni and 5 wt% Co mixed sulphide product that is shipped to Canada and processed by Corefco to produce class 1 nickel, high grade cobalt and byproduct ammonium sulphate fertilizer."

Jan 1, 2017

By Leo H. Duriez, James V. Neuman

THE Bayard property of the united States Smelting Refining and Mining Company is in south central Grant County in southwestern New Mexico about fifteen miles east of Silver City and one mile west of Santa Rita. The present holdings cover a belt roughly one mile wide by ten miles long, lying west of, and adjacent to, the holdings of the American Smelting and Refining Co., Kennecott Copper Corp., Empire Zinc Co., and Peru Mining Co. The area extends from the village of Bayard on the south to a point three miles northeast of Fierro. The property is a part of the well-known Central mining district which has been New Mexico's leading copper-zinc producer for many years. The property is segregated into three sections, the Bullfrog, Hanover Bessemer, and the Shingle Canyon sections. Of these, the Bullfrog section covers the area between the towns of Bayard and Hanover and includes the Bullfrog No. 1, Bullfrog No. 2, Slate, Hobo,

Jan 1, 1948

By C. M. D. Majola, K. E. Langerman

Energy efficiency is a cost-effective way of both bolstering energy security and limiting the harmful effects of energy use on the environment. Mining is an inherently energy-intensive activity, and the 2008 revision of South Africa’s National Energy Efficiency Strategy (NEES) set a target of a 10% reduction in energy consumption by 2015 for the mining sector. In this study, we investigate the effectiveness of the NEES in improving energy efficiency in the South African coal mining sector by surveying energy intensity at a number of operations, and analysing energy efficiency trends and energy use by process and energy carrier at an underground coal mine in Mpumalanga. Most mines surveyed exhibit an increase in energy intensity over time. At the case study mine, the increase was primarily due to increased energy use in the beneficiation and discard reclaiming processes. Trends in energy consumption are a poor reflection of trends in energy intensity, as a decline in energy consumption is most easily achieved by reducing production. A more appropriate metric for energy efficiency at coal mines is energy intensity, defined as energy use per unit of saleable product, relative to a multi-year baseline. The evidence suggests that the NEES has been ineffective in promoting energy efficiency in South African coal mines. We propose that greater success could be achieved by monitoring and reporting on energy intensity at the process level, and by incentivizing energy efficiency gains.

Sep 6, 2023

By V. Gregoire

THE DEVELOPMENT by the Iron Ore Company of Canada of the Quebec-Labrador mining project, which eventually led to 'Iron Ore in 1954', involved, from the start, several distinct undertakings. Among them, the most important were: The construction of a 360-mile railway, linking Knob Lake with Seven Islands. The erection of a railway terminal, and harbour facilities, at Seven Islands itself. The building of an entire townsite at Schefferville (formerly Knob Lake) The construction of two hydroelectric plants; and, finally, The development of a sufficient number of orebodies to enable a production of 10 to 15 million tons of ore a year. Since these phases of the project have already been the subject of previous discussions, this paper will not elaborate further on them but will rather concern itself with a brief outline of the Company's current mining practices.

Jan 1, 1958

By R. Tervo, G. Ellie

"Automated information systems are being developed very rapidly in Europe. In France, Belgium and West Germany, more than 70% of the coal production is controlled by these installations. Information on both product ion and the mine environment is produced. For example, at one mine in France the system records the operating times of the compressors and of the refrigeration pumps, counts the number of coal cars passing the unloading point, and controls the principal conveyors and the loading /unloading of the storage bins. In addition, the ventilation air velocity, the methane content and the carbon monoxide content in the return air entry are recorded; an alarm is triggered and the current to the conveyors cut when the gas content exceeds a critical level. The recorded information is used at four levels: (1) for immediate action, (2) for daily reports, (3) for monthly reports and (4) for long-term studies. For example, when any conveyor is stopped for more than 10 minutes, the system controller immediately telephones to learn of the reason. At the end of a shift, the load factor of the conveyors is computed; then monthly an analysis of the causes of low load factors is made. The presentation describes in detail the system that has been installed in more than 20 mines in France."

Jan 1, 1973

By M Barker, H Li

The total number of tailings accidents has reduced from over 50/decade in the 1960s-1980s to less than 30/decade in the 2000s to 2010s. However, the rate of significant tailings dam failures has not been reduced. The significant tailings dam failures the mining industry experienced in the recent history include: Merriespruit, South Africa, 1994; Los Frails, Spain, 1998; Kolontár, Hungry, 2010; Mount Polley, Canada, 2014; and Samarco, Brazil, 2015. The conventional Factor of Safety approach itself may not be enough to further reduce the rate of significant tailings failures due to its limitations such as uncertainty. For example, the same factor of safety could have a vast range of annual probability of failure for different tailings dams, and insufficient consideration of failure consequence. This paper presents a risk based approach for design with the objective being to minimise tailings dam failures, especially those significant tailings failures with high consequence and low probability. This approach includes risk based design and risk management using bowtie tools. In the risk based design, quantitative analysis will be used to estimate the annual probability of failure and the tolerable failure criteria is linked to the consequence category. Bowtie analyses will be used to understand hazards and risks and identify and select independent controls that are effective in preventing and mitigating catastrophic failures. In this paper, examples of risk based design and bowtie analyses are presented and discussed. CITATION:Li, H and Barker, M, 2018. Risk-based approach for minimising tailings dam failures, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 397–414 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By Richard J. Mainiero

Traditional techniques for the experimental determination of toxic fumes produced by the detonation of high explosives are not applicable to blasting agents. To detonate properly, blasting agents require confinement, a significant booster, charge diameters of 3 inches (7.5 cm) or greater, and charge lengths greater than two-times the charge diameter. Without these conditions, blasting agents will not detonate at full order, leading to a misrepresentation of the gaseous products. A facility for detonating large, confined charges in a controlled volume has been constructed at the Pittsburgh Research Center’s Experimental Mine. The facility consists of a portion of mine entry (once used for full-scale mine explosion research and demonstrations) enclosed between two explosion proof bulkheads. Total volume of the chamber is 9,666 ft (274 m). The chamber is equipped with an air circulating system and is3 3vented using the mine's airflow. Up to 10-pound (4.5-kg) charges can be detonated in the chamber using a variety of confinements. For a typical test, the blasting agent is confined in a 4-inch (10-cm) schedule 80 steel pipe and initiated by a 3-inch (7.5-cm) diameter, 1-inch (2.5-cm) thick Pentolite booster. This combination of confinement and initiation yields a detonation velocity of about 4,000 m/sec for ANFO. This velocity is in line with that measured for blasting in the field. Twenty four 2-inch thick steel plates are suspended around the pipe bomb to stop shrapnel that would otherwise seriously damage the chamber. Following detonation of an explosive in the chamber, a circulating fan is run for about 10 minutes to uniformly mix the chamber atmosphere. Fumes samples are taken out of the chamber through 1/4-inch (0.6-cm) Teflon or polyethylene2tubes for analysis. The fumes are analyzed using bubblers or Vacutainers to collect samples for analysis by the analytical chemistry lab. The technique described here has been employed to determine the fumes produced by the detonation of a variety of ANFO formulations and commercial explosives. This technique may be developed as a standard test to measure fumes produced by blasting agents or may be used to provide data with which to develop a computer model that will reliably predict the expected fumes production based on chemical composition.

By C. J. Hall

This paper presents a basic motive column analysis of natural ventilation and shaft resistance, using the density depth diagram. The method makes use of tables showing the state of the air as determined by thermodynamic analysis. Several theoretical examples are given.

Jan 1, 1968