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By Steve Karl

"The International Tunnelling and Underground Space Association (ITA) held its 42nd General Assembly along with the 2016 World Tunnel Congress (WTC) April 22-28 in San Francisco, CA. The event was co-organized by the Underground Construction Association of SME (UCA). This was the first time the event has been held in the United States in 20 years.As cities demonstrate strong needs in tunnels and underground spaces for public transportation, subway stations, hydroelectric infrastructures and other underground infrastructure needs, the WTC 2016 provided the 2,319 attendees from around the world a unique occasion to discover the latest state-of-the art innovations in urban planning and underground construction projects in the United States and worldwide.The Congress, held in lieu of the UCA’s North American Tunneling Conference, included an exhibit that attracted 226 exhibitors in 298 booths. The exhibit had on display the latest in technical equipment and services from some of the largest and best companies in the international tunneling industry. The exhibit hall was also the place where participants were able to interact with the authors of the 168 posters and receive answers to various topics directly concerning civil engineers: innovative procurement processes, cost and risk management, contractual methods, BIM technologies and examples of innovative underground infrastructures built worldwide. And the technical program included 353 technical presentations – 185 podium and 168 posters.What is ITA?ITA-AITES is a nonprofit, nongovernmental organization that promotes greater use of underground space as a key instrument in sustainable development. Established in 1974 and based in Lausanne, Switzerland, ITA-AITES is made up thousands of professionals involved in the tunnel and underground space industry, including engineers, project owners, town planners, architects, industrial designers, companies specialized in public works and major structures, suppliers of construction site facilities and equipment, lawyers, politicians, researchers and academics, economists, financial experts and other stakeholders.ITA-AITES consists of 73 member nations and 300 affiliated members, including 15 major sponsors and 60 donors. The association is run by an executive council made up of 15 members elected by the 73 member nations, each representing a different dimension of the tunnel community."

Jun 1, 2016

By Richard D. Begley

This paper will present the results of an analysis of several abandoned coal mine projects and includes field data for over a dozen different reclamation projects recently completed in the state of West . Virginia. The analysis was performed with the objective of summarizing and or classification of the environmental consequences with reference to the characteristics of the mining facilities (surface, underground, etc.). The analysis also addressed the itemized cost of remediation with respect to procedures, environmental concerns and time. The results of the analysis are that each abandoned coal mine site in West Virginia have/had many unique features and in most cases include a combination of environmental concerns that complicate comparisons. The study also revealed that the abandoned mine land program for mines abandoned prior to 1977 that is being financed by a tax on the production of coal, has produced many benefits for the state of West Virginia. This grant program administered by the Office of Surface Mining, has resulted in a high quality methodology of remediation that has been successful for many years in greatly minimizing and/or eliminating environmental concerns from abandoned coal mines.

Jan 1, 1997

By P. van der Steen

This paper examines the historical developments in diamond beneficiation technology and the impacts on the industry. The art of diamond beneficiation has given way to the application of scientific process, but at considerable capital expenditure. The shift in beneficiation methodologies has been disruptive to the traditional skills set of the industry, but evolutionary change continues and has been beneficial to the quality of the final product.

Jan 1, 2010

By Mohamad Kharseh

There is general acceptance that climate change, which is the most important challenge facing humanity, is anthropogenic and attributed to fossil fuel consumption. Therefore, improving the performance of our existing energy systems and deploy more renewable energy resources is an urgent issue to be addressed. Geothermal refers to existing of heat energy in deep rock and sedimentary basins. This energy can be used to drive a power turbine to generate electricity. Traditionally, geothermal has been exploited in places with the plentiful hot water at relatively shallow depth. In the light of fact that ground temperature increases with the depth everywhere on the Earth, engineered geothermal systems (EGS) can be installed in any place to exploit the geothermal in generating energy. Unfortunately, the high exploration and drilling costs of boreholes is the main barrier to commerciality of EGS worldwide. In addition, there are technical problems associated with drilling big depth. In oil producing countries such problems can be addressed by utilizing whether active or abandoned oil or gas wells and, consequently, EGS can produce power at profit. The current study presents an analysis of a binary geothermal power generation system for commercial electricity generation in Qatar. For this purpose, two binary cycles are assumed the main difference between them is that the first one is air cooled while the other will be water cooled. The performance of the two cycles and the possibility of improvement has been shown. Economic analysis the power plant shows that the levelized costs of electricity is 3.6US¢/kWh and the pay-back time is less than 8 years.

Aug 1, 2013

By Charles Dumaresq

The management of mine tailings poses a complex range of potential risks, including physical risks, such as the risk of catastrophic failure of a tailings facility and chemical risks such as the risk of long-term leaching of contaminants into the downstream environment. If these risks materialize, they can lead to a wide range of impacts on people and the environment, including human fatalities and severe impacts on downstream ecosystems, and the costs of recovery borne by industry, communities, governments, and society as a whole can be immense. Tailings facility failures in Canada (2014), Brazil (2015 and 2019), South Africa (2022), and in other locations around the world underscore how high the stakes are when mines produce and manage tailings (WISE Uranium Project 2019). Understandably, many people do not trust the mining industry to manage tailings responsibly. As an industry, it is our responsibility to manage tailings in a manner that is responsible and strives to minimize harm associated with tailings management, including effectively managing both the physical and chemical risks associated with tailings. Standards have an important role to play in responsible tailings management by setting expectations for standards of care and providing a means to measure and report on performance. In jurisdictions with strong legal requirements for tailings management, standards play a complementary role, pushing performance improvements in areas that may be difficult or impossible to address in legal requirements. In jurisdictions where legal requirements are lagging, standards may represent the de facto leading practice and may be the primary tool to help ensure responsible tailings management. Implementation of standards can help companies demonstrate that tailings are being responsibly managed and help build trust and credibility. Most importantly though, standards are important tools to help ensure that the risks associated with tailings are reduced, and that remaining risks are effectively managed. However, we must recognize that conformance with standards can have a down-side – the proverbial two-edged sword. Having standards is vital but there is a risk that implementing standards becomes a “box checking” exercise, with ongoing conformance leading to complacency. We must not allow ourselves to fall into the trap of believing that, just because we are complying with applicable standards and laws, we are therefore doing our best, and that “it can’t happen to us.” In addition, if conformance becomes the goal and the standard does not have mechanisms to drive continual improvement, then once the standard is met, there may be no incentive to improve. The point of complying with standards is not to pass the test. The point is to manage tailings responsibly, prevent catastrophic failures, and minimize harm. The point is to do better, because we must do better. To do that, we need to strive not for conformance, but for excellence in tailings management, driven by continual improvement and a quest to do better.

Feb 1, 2025

By J. J. Fitzpatrick

"This paper deals with the methods used by Quebec Cartier Mining Company in the evaluation and selection of new haulage equipment and in increasing the productivity of the existing fleet.Selection of new equipment is based upon the comparison, for each model under consideration, of the capital investment required and the estimated operating costs and production rate. The calculation of the production rate is based on a widely used estimating procedure. Actual operating conditions considered in the method include: payload, haul distance, road grade, rolling resistance, loading and dumping times, and operational efficiency. A digital computer is used to handle the large volume of repetitive calculations required. Where a fleet of haulage equipment includes trucks of different size and performance characteristics, the problem exists of assigning each truck type to the different working locations to minimize total cost. Linear programming can be used in the solution of this problem."

Jan 1, 1967

The Bibliographic Data Base is the result of a literature search con-ducted as one task of the technology assessment of current and advanced logging techniques, sponsored by the United States Bureau of Mines. After compilation, the bibliography was converted to an automated form for ease of utilization, and to allow for maintaining and updating the data base. The data base covers articles, symposia, books, patents, corporate and government reports, and other literature concerned with some aspect of borehole logging from January 1969 through December 1975. Periodic up-dating will be necessary to keep the data base contents in step with developments in the rapidly advancing field of application of borehole logging to mining. Many bibliographic indexes were scanned for entries relating to the subject of interest, and those entries which were included in our data base contain a reference to the bibliographic index in which they were listed (see Section 2.4.7). With the aid of these indexes, a vast number of publications, including foreign reports and publications, have been scanned for works relevant to borehole logging technology.

Jan 1, 1976

By T. F. Deems

The nature, usage and comparatively rare occurrence of ball clay is described. The importance of these white firing plastic clays in ceramics, particularly in the production of industrial sanitary ware and tiles, is emphasized. The US deposits are briefly discussed. What is known about relevant deposits in Brazil, Argentina, Colombia and Venezuela (the four largest ceramic producers in South America) is also described. The ceramic plants have been sited near the centers of population rather than the plastic clay deposits. At present, extraction is probably concentrated on surface residual deposits and lenses which require minimum investment. Native plastic clays are used exclusively in the tile plants, but in sanitary ware, they are often used as extenders of imported ball clays.

Jan 1, 1997

By Yuemin Zhao, Wenxuan Liu, Maoming Fan, Zhanyuan Long

"Coal is mainly composed of energy-producing elements carbon and hydrogen. In addition to these elements, coal usually contains many other valuable elements, including iron, aluminum, silicon, rare earth elements, lithium, gallium, germanium, vanadium, uranium, titanium, scandium and phosphorus. These coalassociated elements are significantly enriched in coal combustion byproduct fly ash because the majority of the main components, carbon and hydrogen elements, being removed. Table 1 provides the chemical composition range of the main element oxides in 12 Chinese fly ash samples collected from coal power plants located in Northeast China, Northwest China, Southwest China and Southeast China. It can be seen from Table 1 that the major mineral components of different ashes are similar, but the bulk chemistry of different fly ashes may vary due to the changes of ratios of the mineral components in different coals. The major mineral components in various Chinese coal combustion fly ash are silicates, iron oxides and unburned carbon.Chinese coal fly ash usually contains about 5 to 15 percent of unburned carbon, which are generally chars with irregular shapes and wide particle size distribution. In addition to unburned carbon, XRD analysis of four Chinese fly ash samples from Liaoning, Shanxi, Guizhou and Shandong provinces indicates that the fly ash samples are composed of minerals such as quartz (SiO2), mullite (3Al2O3.2SiO2 or 2Al2O3.SiO2), hematite (Fe2O3), maghemite (gamma form of hematite, ?-Fe2O3) and magnetite (Fe3O4). The mullite and quartz particles are usually present as spherical particles because they are formed by melting clays, feldspars, quartz, calcite and other common minerals in coal during coal combustion. The silicate particles have usually entrapped gas to yield hollow spherical particles because their lower melting point facilitates gas entrapment.The iron oxides are usually spherical also. The magnetite (Fe3O4) is derived from pyrite (FeS2), hematite (Fe2O3), siderite (FeCO3) and limonite (2Fe2O3.3H2O) in the coal. Maghemite (?-Fe2O3) is formed by dehydration of the mineral hydrohematite (?-FeO(OH)) and/or oxidation of magnetite (Fe3O4) during coal combustion. Maghemite (?-Fe2O3) and magnetite (Fe3O4) are strongly magnetic, so they are recovered from Chinese coal fly ash and widely used for coal processing in China (Fan et al., 2005, 2000)."

Jan 3, 2018

By R P. Douglas

During 1955, Cominco commenced an exploration pro-gram in northern New Brunswick; in the following year, what is now the Wedge mine was discovered. The mineralization is mainly pyrite, with associated chalcopyrite and minor amounts of sphalerite and galena. The property was brought into production at 750 tons per day in early 1962. The ore is trucked 10 miles to the Heath Steele concentrator, where a copper concentrate grading about 19.5 per cent is produced and shipped to the Japanese markets through the port of Dalhousie, New Brunswick. Introduction THE Wedge mine, owned by The Consolidated Mining and Smelting Company of Canada Limited (Cominco), is located in the Newcastle-Bathurst area of New Brunswick. It is 42 miles by road northwest of Newcastle and 37 miles southwest of Bathurst (Figure 1). The mine is located on the north side of the Nipisiquit river in one of the more mountainous areas of the Province, the local relief rising to 1,500 feet above sea level. There is an almost complete forest cover of mixed hardwoods and conifers -the val-leys and hillsides being covered by balsam, spruce and pine, the swamps by cedars and black spruce and the highlands by mixed hardwoods.

Jan 1, 1965

By CIM Standing Committee

The CIM Definition Standards on Mineral Resources and Reserves (CIM Definition Standards) establish definitions and guidance on the definitions for Mineral Resources, Mineral Reserves, and mining studies used in Canada. The Mineral Resource, Mineral Reserve, and mining study definitions are incorporated, by reference, into National Instrument 43-101 – Standards of Disclosure for Mineral Projects (NI 43-101). The CIM Definition Standards can be viewed at mrmr.cim.org. Readers should be aware that reports written by persons issuing technical reports that disclose information about exploration or other mining properties to the public in Canada are governed by a number of securities regulations.

May 10, 2014

The Graham Farmer Freeway Project in Perth, Western Australia, is the largest urban infrastructure project ever carried out in the State. At a project cost of over $360 million, it also ranks as one of the largest in Australia and is even large by world class standards. The project provides a much needed east-west freeway bypass around the CBD of Perth, linking the Great Eastern Highway in the east with the Kwinana and Mitchell Freeway system in the west. The Bypass will have 6.5 kilometres of freeway, a major bridge over the Swan River, several pedestrian overpasses and underpasses, dual use paths, interchanges and flyover bridges and a rail tunnel. The whole project is being carried out over a four-year time frame, due to be complete and open to traffic in June 2000. The project has been divided into two stages, with Stage 1 including the 1.63 kilometre long Northbridge Tunnel, the subject of this paper.

Jan 1, 1999

By C. D. Harrison

The 1990 Clean Air Act Amendments specify national objectives for reducing sulfur dioxide emissions from coal-fired power plants System-wide reductions can be achieved by combining various emissions controls technologies and allowances, or compliance credits, that can be purchased, sold, or traded. As part of the Coal Quality Expert development project funded by U.S. Department of Energy and the Electric Power Research Institute (EPRI), Black & Veatch has developed an interactive computer tool, the Acid Rain Advisor (ARA). ARA allows the user to develop integrated system-wide compliance plans by comparing the costs and emissions reduction benefits for emissions allowances and various SO2 control technologies such as coal cleaning, fuel switching, and scrubber retrofits.

Jan 1, 1992

By Gordon G. Duncan

Historical Sketch Occurrences of native copper have been known along the Arctic coast of Canada, especially in the vicinity of the. Coppermine river, since the early part of the eighteenth century (See map, Figure 2, insert). In 1769, Samuel Hearne, a clerk of the Hudson's Bay Company at Fort Churchill, was sent to explore the 'copper mines' from which natives had been reported to secure copper for tools, fishing spears, etc. After two successful attempts, he reached the Coppermine river in 1771, accompanied by Indian guides. This hazardous trip was indeed a remarkable feat when one considers the vast distance covered, a great deal of which was barren lands. At Bloody falls, (See Figure 1) on the Coppermine river, Hearne's Indians swooped down on a party of sleeping Esquimaux, who gathered there each summer to fish, and murdered the entire band encamped on that side of the river. Hence the name of the falls. Hearne's knowledge of minerals was undoubtedly limited. He reported having seen the copper mines from which the natives were securing the copper, but he failed to prove the economic possibilities of the copper occurrences or to give an accurate description of any deposit. Sir John Franklin visited the area in 1821. He and other members of his expedition, namely, Richardson, Back, Kendall, and Hood, reported native-copper float to occur in the vicinity of the Coppermine river and Bathurst inlet.

Jan 1, 1931

By J T. Carswell

Best practice mine sampling should provide a detailed quantification of all potential sources of error at each stage of sampling, sample preparation and assaying.Quality assurance (QA) should include testing for and quantifying potential sampling errors, and should be the basis for establishing ongoing sampling protocols, should set error limits and define quality control (QC) procedures. QA should be within the framework of Theory of Sampling (TOS) but may not involve the estimation of the sampling constant and the application of Gy’s formula.Best practice QC should be carried out efficiently and in a timely and cost-effective manner with regular reporting against the guidelines established by QA.This paper provides an assessment of, and checklist for, current best practice sampling QA/QC with examples from operating gold mines including the QA/QC of underground (UG) reverse circulation (RC) grade control.CITATION:Carswell, J T, 2017. Best practice sampling QA/QC for gold and base metal mining – including how to assess the applicability of underground reverse circulation grade control sampling, in Proceedings Tenth International Mining Geology Conference 2017, pp 297–304 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By Joo Hyun Park, Soo Sang Park

The distribution behavior of Pb between molten copper and FetO-SiO2 (-CaO, Al2O3) slags was investigated at 1473 K (1200 oC) and p(O2)=10-10 atm in view of the reaction mechanism of Pb dissolution into the slag. The distribution ratio of Pb (LPb) decreases with increasing CaO content (~6 mass pct) irrespective of Fe/SiO2 ratio (1.4~1.7). However, the addition of alumina into a slag with Fe/SiO2=1.5 linearly decreases the LPb, whereas a minimum value is observed at about 4 mass pct Al2O3 at Fe/SiO2=1.3. The log LPb continuously decreases with increasing Fe/SiO2 ratio, and the addition of Al2O3 (5 to 15 mass pct) into the silica-saturated iron silicate slag (Fe/SiO2 < 1.0) yields the highest Pb distribution ratio. The log LPb linearly decreases by increasing the log (Fe3+/Fe2+) value. The Pb distribution ratio increases and the excess free energy of PbO decreases with increasing Cu2O content in the slag. However, from the viewpoint of copper loss into the slag, the silica-saturated system containing small amounts of alumina is strongly recommended to stabilize PbO in the slag phase at a low Cu2O content.

Jan 1, 2014

By H. W. Gillett

MAINTENANCE of membership by the technical so¬cieties and the activity of these societies in spite of the adverse business situation have been noteworthy. This forcibly brings home the fact that industry recognizes that sound technical guidance is well worth its cost. The numerous difficulties and losses due to defects of various kinds arising from gas-metal reactions are now generally recognized and interest in these problems is widespread. The forthcoming A. I. M. E. round-table discussion of gas-metal problems will do much to clarify the situation and will permit us to assay our present knowledge and to suggest the proper direction for profitable future research. "The Age Hardening of Metal" was the title of the annual I. M. D. lecture delivered by Dr. Paul D. Merica. A critical review of the known facts relating to age-hardening phenomena was first given, followed by the presentation of a theory correlating the detailed observations which have been made regarding the mechanism of the hardening.

Jan 1, 1933

In its largest product launch in company history, Cummins Engines welcomed more than 200 customers, vendors and media to witness the unveiling of its new QSK95 engine at its Seymour Engine Plant in Seymour, IN on Nov. 1. It took the efforts of 150 engineers to design the QSK95 and more than $100 million in investments to establish a new production line and test facility at Cummins? Seymour Engine plant. The result of these efforts is a new platform of engines that Cummins says will provide as much as 2,983 kW (4,000 hp) and will be the most powerful, high-speed diesel engine ever built.

Jan 1, 2012

By Chris G. Dobson

Introduction The Britannia mine is at Britannia Beach, on Howe sound, approximately thirty miles from Vancouver. The first claims were staked in 1898, and a local company was formed at that time to develop them. In 1904, Mr. Grant B. Schley became actively interested in the property and in the following year the Britannia Mining and Smelting Company, Limited, was incorporated to operate it. This Company was taken over a few years later by the Howe Sound Company, Limited. The mine comprises five more or less separate ore-bodies, which have produced approximately 20,000,000 tons of ore to date. The East Bluff ore-body, with which the present paper deals, is well suited to large-scale mining by means of carefully placed powder blasts. It covers approximately an acre and lies in the slate footwall, in a bay produced by a fault. The hanging-wall side, on the west, forms the face of the Bluff glory-hole, which extends to the 1,200 level. A portion of this ore was available for breaking into this old glory-hole, below which four bulldoze chambers could quickly be built. Mining of this block is complicated by a very soft footwall, which &apos;runs&apos; badly when broken. In stoping, care is taken to guard against the hazard of dilution by deliberately leaving a small portion of ore on the footwall. Some of this will undoubtedly be lost, but it is hoped to recover a fair amount of it after the major drawing is completed. The deposit occurs in a greenstone which has been highly silicified following brecciation. The chief minerals are chalcopyrite, sphalerite, and pyrite. Concentrates of copper, zinc, and pyrite are made at the mill. The average grade of ore runs 0.7 per cent copper, 1.5 per cent zinc, and 0.03 oz. gold per ton. The rock, which is practically a chert, is extremely hard, but shatters well. Both in stoping and drifting, holes must be closely spaced and powder used generously. Development When development work started in the East Bluff, there were no raises and only one drift on each level in this section of the mine. After blocking out the ore by thorough diamond drilling, a production of two thousand tons per day was set as a goal. To obtain this tonnage from so small an area required a great deal of carefully planned and well timed development work.

Jan 1, 1935

By Nilmani M, Malone J, Taylor RN, Floyd JM, Gray NB, Fountain CR

CSIRO staff and University of Melbourne staff and students collaborated in an intense programme of investigation on the CSIRO 50 kg Sirosmelt pilot plant.In two days of operation copper matte converting and zinc slag fuming trials were performed, whilst investigation of the process dynamics and process chemistry was carried out. This exercise is an example of the techniques available for process evaluation, which can rapidly advance the understanding of pyrometallurgical operations by use of a team approach covering a wide range of experiments.

Jan 1, 1985