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This field guide is designed for use in planning pollution control and reclamation activities on small sand and gravel operations. Its purpose is to assist operators in selecting environmentally desirable pollution control and reclamation procedures based upon their particular mining situation. The guide includes information on interpreting physical and cultural factors that must be considered in planning and implementing a mining and reclamation program, achieving environmental protection objectives, and improving community/industry cooperation. Included as appendices are a summary of state laws and a list of additional readings on the subject.

Jan 1, 1981

By María Julia Ubillús Mellet

El presente texto complementa el estudio de las estrategias de seguridad en las empresas mineras a través de la alienación de las herramientas de gestión humana en una cultura de seguridad y prevención competitiva, de forma que se mejore el estilo de gestión en seguridad de los equipos gerenciales en las empresas mineras, y se desarrolle un manejo adecuado y responsable entre el área gestión humana y cultura organizacional. En ese sentido, la excelencia de gestión en seguridad radica en que el elemento humano se conecte de forma sistemática a las estrategías que la organización plantee.

Sep 12, 2005

By J Pric, M Fulton, C Xia

A cyanidation study was conducted on a mild refractory gold ore sample from the Central zone of Clarence Stream Property, owned by Freewest Resources Canada, to develop a leaching strategy to extract gold. Gold, at a grade of 8.00 g/t, is present as native gold, electrum and aurostibite. The ore also contains 2.8 per cent pyrrhotite, together with several antimony minerals (0.8 per cent berthierite and gudmundite, 0.18 per cent native antimony and stibnite). It also exhibits weak preg-robbing properties with 0.16 per cent organic carbon. Aurostibite, a gold antimony compound, is particularly known to be insoluble in cyanide solution. The antimony dissolves in cyanide solution to form antimonates, which retards gold dissolution. Industrial practice of extracting gold from aurostibite generally consists of producing a flotation concentrate, which is leached in a pipe reactor at low alkalinity and high oxygen pressure with about 20 g/L cyanide. The proposed new approach is efficient and allows the extraction of gold directly from an ore at atmospheric pressure and a low cyanide concentration at pH 10.5. The effects of grinding, pretreatment, lead nitrate, kerosene and cyanide concentrations have been investigated. The maximum gold extraction obtained on the ore was 87.9 per cent using 800 ppm NaCN, 500 g/t lead nitrate, 30 g/t kerosene, DO 10 ppm and pH 10.5 in 168 hours. The associated cyanide consumption was 1.3 kg/t. The additions of lead nitrate and kerosene increased gold extraction. In comparison to a P80 of 74 ¦m, a P80 of 30 ¦m significantly increased gold extraction. Gold in solid solution in gudmundite and arsenopyrite was believed to be responsible for the unleached fraction until mineralogical analysis of hydroseparation concentrates of leach residues showed that most of the unleached gold occurs as aurostibite, either as locked grains in sulfides/sulfarsenides or as grains with passivation rims of an Au-Sb-O phase. Coarse gold was also found. Gold extraction was not sensitive to cyanide concentration from 250 ppm to 1200 ppm NaCN and high pH was detrimental. Decreasing the cyanide concentration reduced the cyanide consumption to 0.85 kg/t. The removal of coarse gold using a Knelson concentrator and a Mosley table prior to leaching increased the gold extraction to 90.4 per cent (leach residue at 0.77 g/t).

Jan 1, 2007

By Wolfgang G. Brunner

A 3800 m long temporary water-retaining dike has been constructed under extreme conditions in the harsh northern climate to enable two of the kimberiite pipes at the Diavik Diamond Project reserve to be mined using open pits. The Diavik Diamond Project is located on East Island at Lac de Gras in Canada's Northwest Territories, approximately 200 kilometres south of the Arctic Circle. The dike which has been constructed in up to 25 m deep water from crushed granite quarried from the site projects into Lac de Gras encircles the first two of the kimberiite pipes to be mined. An 800 mm wide diaphragm cut­off wall constructed of bentonite, cement and crushed rock, totalling 33,000 m2, and a two-phase jet grouted curtain wail at its base, totalling 8,400 m2, have been installed through the dike and underlying till foundation into bedrock. The cut-off is designed to minimise water seepage from Lac de Gras through the dike. In order to ensure that the dike had adequate internal stability and diaphragm wall construction could proceed safely, the crushed rock fill material dumped into the lake was first compacted by TR 75 deep vibrators. In 2000, Bauer Maschinen GmbH of Schrobenhausen, Germany were awarded the contract for the supply of all specialist foundation equipment required on site and for providing technical support to the Canadian main contractor Lac-de-Gras-Construction throughout the construction of the cut-off walls during 2001 and 2002. Installation of the cut-off walls was completed in July 2002, three weeks ahead of schedule, and dewatering of the inner dike areas commenced just 5 days later and has continued throughout August and September. After completion of extensive testing of the diamond recovery plant, the mine is scheduled to go into full open pit production in February 2003.

Jan 1, 2003

By Alan: Moore Richards

Effective control of airblast requires that significant factors be identified and satisfied by blast design and careful implementation. Significant factors include charge mass, distance, face height and orientation, burden, spacing, and initiation sequence, stemming height and type, topographical shielding, and meteorological conditions. This paper utilizes case histories of blasting in Australian open pit mines to demonstrate techniques that have been used to control airblast to applicable limits.

Jan 1, 2006

By Mark R. Svinkin

Construction vibrations may adversely affect surrounding buildings and their effects range from human discomfort and disturbance of sensitive devices to visible structural damage. There is no unique conclusion regarding the effect of construction vibrations at every site. Measurement is usually made to monitor vibrations and control them with the vibration thresholds for disturbance of sensitive objects as well as damage to structures. To prevent potential litigation and mitigate the vibration effects on sensitive devices, people and structures, it is necessary to manage and minimize vibration problems before the beginning of construction activities or installation of vibrating machine foundations, and during construction. Pre-construction damage survey and engineering vibration investigations, including the prediction of anticipating vibrations, have to be made at most construction sites in advance of construction activities. Vibration monitoring and control have to be provided during construction. The instrumentation feedback of vibration prediction, monitoring and control provide the basis for choice of measures to prevent or mitigate vibration problems and settlement damage hazards.

Jan 1, 2002

By S. Hunt, D. de Vries

Kansanshi Copper Smelter began operation in March 2015. The smelter features a single Isasmelt furnace for smelting, one 6-in-line electric furnace for matte-settling and slag-cleaning duties, four Peirce- Smith converters and two rotary anode furnaces. A 1,450 t/day oxygen plant and a 4,085 t/day sulphuric acid plant are included in the smelter operations. This paper gives an overview of the operational performance to date with summary data for each smelter section. Challenges such as an unforeseen refractory failure in the Isasmelt furnace in 2016 are discussed. Design improvements around the electric furnace are mentioned. Plans for potential future improvements are put into context. A consistent focus on operations, maintenance and continuous improvement has seen the smelter easily achieve its nameplate capacity of 1.2 million tonnes per annum of copper concentrate throughput. The smelter now operates consistently at a concentrate throughput rate of 1.38 million tonnes per annum of copper concentrate. INTRODUCTION The smelter was commissioned in March 2015. Design and commissioning of the smelter have been discussed by de Vries, Hunt, Hanschar and Louie (2016). The smelter rapidly ramped up to achieve nameplate production (1.2 million tonnes per year concentrate) and in 2018 operated consistently at the rate of 1.38 million tonnes per year concentrate. This paper presents major operational data for each section of the plant and describes significant events and improvements during the first four years of operation. The smelter flowsheet is shown in Figure 1.

Jan 1, 2019

By Tracy Brettmann

In recent years the Augered Cast-In-Place (ACIP) Pile industry has seen a substantial increase in the quality control options available to Contractors, Engineers, and Owners. Quality control methods range from the simple, manual techniques that have been used for years to new computerized installation monitoring equipment and nondestructive testing methods. Our ability to monitor and test ACIP piles has grown to such a degree that the industry is struggling to determine how much quality control is enough. This paper reviews the many options available and describes the pros and cons of each. The various nondestructive testing methods, in particular, have been difficult to apply reliably due to misapplications of methods and misinterpretation of the results. ACIP piles have unique properties that require the various nondestructive testing methods available be considered very carefully in determining the method most appropriate for a particular use. Some nondestructive testing methods, as well as automated monitoring equipment, potentially can be applied effectively to increase the level of quality control for ACIP piles. The experience gained on real projects using these new methods, in conjunction with the old procedures, provides valuable information for future applications.

Jan 1, 2000

By John S. Hutchins, David L. Wassum

Mining engineers are ready to take a big step into a new field-oil mining. To understand the subject, one must look at the world's oil supply and demand as well as petroleum technology successes and failures. The US has an abundance of solid hydrocarbon and uranium energy resources, but 75% of its energy for industry, transportation, manufacturing, and space heating comes from liquid petroleum and natural gas. So there are increasing efforts to discover new oil reserves; today the number of drilling rigs operating in the US is at an all-time high. But with 80% of the world's wells already located in the US and Canada, good new exploration prospects are difficult to find. The cost of drilling deep new wells has also greatly increased. The US faced a similar situation in the early 1950s, when primary oil production declines began. During that time, the petroleum researcher introduced secondary recovery techniques such as water flooding and gas injection. This increased the average amount of extractable oil from discovered US reservoirs from 17% to 33%. Production soared and the world petroleum price remained stable until the end of the 1960s. Secondary recovery techniques were then supplemented by tertiary oil recovery technologies-increasing sweep efficiency with such things as CO2 injection-that are, so far, only partially successful in most petroleum fields. Even so, these technologies could raise cumulative recovery expectations to 35-38%. The "lost" oil in depleted US reservoirs equals 48 km3 (300 billion bbl) of conventional oil, or 12 times the current recoverable reserve base. At the present rate of US consumption-1 km3/a or 6 billion bbl/a-this is enough to run the US for 50 years without importing any oil. Moreover, there are 16-24 km3 (100-150 billion bbl) of as-yet unrecoverable heavy oil and tar sands in the US.

Jan 12, 1981

The consideration of environmental constraints and issues is a fundamental component of all stages of planning, development, operation and decommissioning mining and quarrying projects. Provision needs to be made at all stages for the cost of environmental components since it is of fundamental importance that they be recognised as an integral component of any project. This paper presents an approach to environmental costing, suggested levels for budgeting, and the cost benefits.

Jan 1, 1990

By S E. Munro, P D. Munro

The commonly traded base metals concentrates of copper, lead, tin and zinc are sold by miners to custom smelters using contracts whose terms were generally established at the beginning of the 20th century or even earlier. Technical clauses in these concentrates for items such as payable metals and penalty elements do not reflect current realities of extractive metallurgical technologies and hygiene/environmental issues.It is an axiom that the miners and smelters have a symbiotic relationship. While the existing antique and arcane commercial arrangements serve the purpose of transferring money from the buyer to the seller, they are not likely to result in the industry achieving better overall technical and economic outcomes. By examining the cases for copper concentrates and zinc concentrates in particular, it will be shown that the practical application of these antiquated technical clauses does not drive the miners to produce the better quality concentrates that should be desired by the smelters. This is despite development of mineral beneficiation and hydrometallurgical technologies that would allow the miners to make better products.The adage that any extractive metallurgical problem in the smelter is cheaper to solve in the concentrator still generally holds.While nickel concentrates are only touched on lightly in this discussion because sales terms are more opaque than those for the other base metals, it is expected that the same conclusions will apply.CITATION:Munro, P D and Munro, S E, 2015. Base metals concentrate sales contracts – change Pavlov and the dog, in Proceedings MetPlant 2015, pp 46–60 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By Pavel Vasak

The Laurentian University Virtual Reality Laboratory (VRL) has provided a unique platform for the development and testing of novel seismic and microseismic data processing and visualization technology. In collaboration with Vale?s Creighton Mine, the technology was implemented at the mine site and consists of a VRL system and site calibrated Seismic Excavation Hazard Map (SEHM) software. The SEHM was developed as a practical solution for the mine operator to identify areas of elevated, active rock mass damage processes caused by recent mining activity. This paper is a pictorial representation of the 3D stereoscopic demonstration of the Creighton Mine seismic data distribution and interpreted SEHM for the first quarter of 2009. A live demonstration is scheduled at the Laurentian University VRL as one of the conference field trips. The demonstration highlights the technology transfer of research concepts into a near-real-time excavation hazard system that utilizes the key aspects of virtual reality technology; the ability to integrate large datasets (geology, mine excavation, (seismic) monitoring data, production scheduling, stress model, etc.); the ability to manipulate and visualize large datasets in both space and in time (mining sequence); and the ability to review the datasets by a group of experts in an immersive (3D stereoscopic), collaborative environment to better understand the processes and context of the mining-induced seismicity and evaluate potential risks to the mining operation.

Oct 1, 2010

"The Ernest Henry Mining (EHM) ore body is an iron oxide copper gold deposit with an average grade of 1.1 percent copper, 0.5 g/tonne gold and 22 percent magnetite. At the end of 2009, EHM converted the ball mill media charge from forged steel to high chrome media. At high pH values (above 10.5), forged media is passivated, so as the pH of the system drops the media corrosion rate increases and floods the system with corrosion products, affecting flotation. As the high chrome media is much more inert, pH has less of an effect on copper flotation response. Given this, the pH in the roughers was dropped from 10.6 to 9.6 and it was found that there was a slight increase in copper recovery and no statistical change in either the rougher or final copper concentrate grades for copper and gold. With the reduction in pH, there was a noticeable reduction in lime usage from 0.85 kg of lime per tonne of ore processed to 0.55 kg/t. This reduction in lime is equivalent to approximately $700,000 per annum at current production rates.INTRODUCTION The Xstrata Copper Ernest Henry Mine (EHM) is situated 38 km north east of Cloncurry, Australia. The mine began as an open-cut operation in 1998 and transitioned to a multi-sourced operation in December of 2011, utilising ore from the newly completed underground mine in addition to ore mined from the Mount Margaret Mining operations. EHM produces a combined copper gold concentrate containing 25 000 t of copper and 35 000 oz of gold annually, utilising a three stage grinding circuit along with a four stage flotation circuit. In addition to this EHM also produces 1 000 000 t of magnetite concentrate annually via a further grinding and three stage magnetic separation circuit. Based on metallurgical test work performed by Magotteaux between 2002 and 2008, the step to change from forged steel media to 18 percent chrome media was taken in 2009 in a bid to alter the pulp chemistry to improve the flotation performance in the plant (Greet, Kinal, Twomey, & Peatey, 2010). This plant trial resulted in: • Increased dissolved oxygen levels within the pulp, • A ball mill discharge Eh shift of 25 mV to more oxidising pulp potentials, and • An EDTA extractable iron percentage reduction. These improvements in the pulp chemistry resulted in an increase of 1.7 ± 0.6 percent in copper recovery and an increase of 2.9 ± 1.7 percent in gold recovery. As the plant trial using high chrome media was successful, the use of the media was adopted as the standard for the ball mill. This implementation opened the door for further process improvements around the flotation circuit."

Jan 1, 2014

By I. J. Barker

Keywords: Submerged-arc furnace, plasma furnace, d.c. furnace, scale up, Søderberg electrodes, smart grid, demand side management, load shedding This paper argues that the scale up of furnaces and the supply of electricity are going to be two major issues that will affect the ferro-alloy industry in the near future, and that economic factors will drive this development. The most common type of furnace for producing ferro-alloys at present is the submerged-arc furnace with three electrodes, fed from a three-phase a.c. electrical supply. The scale up of this technology has now reached a fundamental constraint, which is caused by the electrical reactance of the secondary circuit. If the economy of any further scale up is to be achieved in the future then a different technology will have to be used. The supply of electrical power in future is likely to become a more complex issue than it is at present. Existing submerged-arc furnaces tend to run at fairly steady loads, but the ability to swing the load under demand-side management may offer advantages, and may allow a furnace to get cheaper power from the organisations that supply this power. This will have to be counterbalanced against the nuisance factors incurred by having a varying load in the operation of the furnace. Various options are therefore discussed in this paper. The possibility of scale up of Søderberg electrodes is discussed, as well as the use of d.c. power and multiple electrodes. Some of the issues with load swinging are also examined. A particular scenario is also briefly presented to show that considerable further scale up of ferro-alloy furnaces is still possible.

Jan 1, 2011

By A. D. S. Gillies

Diesel engine particulate matter pollution is a matter of concern currently in underground mines worldwide. A number of real-time Diesel Particulate Matter (DPM) monitors have been developed in recent years; two of these by the National Institute of Occupational Health and Safety (NIOSH) in the US. One, the D-PDM, is based on an adaption of the successful NIOSH?s Personal Dust Monitor (PDM) unit which is being taken up very successfully for mine respirable dust monitoring. The D-PDM measures all particulate matter within a sub-micron range as classified nominally at 0.8 micrometers by a purpose developed cyclone. The other, the FLIR Airtec, measures the Elemental Carbon (EC) component of DPM by a laser scattering approach. Both instruments have been evaluated underground in robustness and reliability testing in coal mines by the authors. Real time DPM monitors allow greater understanding of the sources and levels of DPM pollution in underground activities. They allow engineering evaluations to determine how conditions can be improved or mining personnel relocated to lower concentration levels. Studies are discussed that examine DPM concentrations from vehicles under varying ventilation conditions. Some of these concern tests undertaken during high activity longwall face moves. They focus on evaluating DPM during the various phases of the face Chock Shield moves. An initiative in some mines has been to limit the number of vehicles in the mining section or panel by the use of a Tag Board or Traffic Controller at the panel travel road entrance to manage exhaust DPM and gases. Diesel tags or tokens are used to control the number of vehicles entering a section or panel and so limit level of pollution. Summation of DPM levels from points monitored throughout a panel demonstrates increasing DPM levels from influence of additional equipment in series within the ventilation circuit. An alternative approach is to invest in underground continuous real-time monitoring of exhaust gases, DPM and section air quantity and integrate this information to determine whether an additional vehicle can enter without exceeding diesel target limit. This optimizes the access of diesel vehicles and replaces the existing manual tag board system. Real-time DPM monitoring allows the industry to pin-point high exposure zones such as those encountered where various vehicles work in areas of constrained or difficult ventilation. Identification of high DPM zones allows efficient modification of mine ventilation, operator positioning and other work practices to reduce underground miners? exposures.

Jan 1, 2012

By Adrian Moore, John Wilson, Alan Richards, Emad Gad

Project C9040 – ‘Structure Response to Blast Vibration’, funded by the Australian Coal Association Research Program (ACARP), involved the investigation of the structural response from blast vibration of three houses of brick veneer construction subject to a wide range of ground vibration levels. This paper summarises the findings of a house subject to vibration levels up to 220 mm/s (8.7 in/s). Damage attributable to blast vibration was not observed until vibration levels exceeded 70 mm/s (2.8 in/s).

Jan 1, 2003

By Steve Collinsworth, Nils Heinke

In 1989, I realized the definite need for change in the Blast Hole Drilling Industry. With over 25 years of experience in dealing with the industry, I am well inGormed and educated concerning the problems that occur in Blast Hole Drilling. After continues interaction with the Drill & Blast Superintendents, Drillers, Purchasing Agents, Mechanics, and others in the field, a basic understanding was developed as to the origins of the main problems that the industry f&s with their drillings programs.

Jan 1, 1997

By Jeffrey L. Pagnutti

Train derailment can lead to loss of capital, damage to the environment, and loss of life. Machinery condition monitoring techniques can be used to develop a structural health monitoring system for railway track to detect faults at the incipient stage, before catastrophic failure occurs. This study uses vibration measurements from a novel material haulage unit to develop a decision support system for railway track maintenance. A variety of feature sets and classifiers were compared to determine the optimal configuration for fault detection. The results highlight the shortcomings and advantages of certain methods and describe the process in which the optimal result was obtained. The Parzen data descriptor paired with a refined statistical feature set performed the task of fault detection with less than five percent false positive and false negative classification error. Overall, the outcome of these experiments indicated that condition monitoring of railway systems is a promising approach for fault detection and has the potential to avoid catastrophic failure.

May 1, 2013

By John Watson

New Technologies, New Challenges and New Opportunities For quite some time now, numerous explosive manufacturers have spent untold man-hours and millions of dollars trying to develop a blast initiation technology that would “once and for all” provide users with what was once believed to be only a theoretical possibility...nominal timing. Zero “cap scatter” (the amount of variation of delay timing from the targeted nominal) has been the industry’s goal ever since delays were first introduced into the marketplace. Just as adding delay time between blast-holes improved blast performance since their introduction, having the wrong delay or a poorly timed blast has proven to be very inefficient and in many cases hazardous. The question of how precise a blast initiation system needs to be still remains unanswered, but electronic detonator systems being used today indicate that significant improvements can be achieved over conventional pyrotechnic detonators. These systems can typically provide single digit millisecond ranges of variability, if not sub-millisecond in some cases.

Jan 1, 2003

By Ajoy K. Singh, B Mohanty, P K. Singh

A study was conducted to investigate the damage potential to underground multiseam openings caused due to vibration generated by open-pit coal mine blasting. The objective was to recommend optimal explosives weight per delay to be detonated in open-pit blasts to ensure the safety and stability of underground openings. Sixteen blasts with varying charge weights and initiation sequences were conducted at Samleshawari open-pit mine and eighty four blast vibration data were recorded in the Hingir Rampur underground colliery in India. Analysis of vibration data showed that roof of the underground openings vibrated with much higher amplitudes compared to those in pillars and floors. The amplifications of vibration in the roof at the junction were upto 4.3 times the pillar vibration. It was observed that coal chips detached from roof when the peak particle velocity reached 131 mm/s or higher. The vibration magnitude recorded was higher in upper-seam openings than in belowseam openings. Rapid attenuation of vibration was recorded in below-seam openings at similar locations. Appropriate particle velocity-charge weight-distance equations were established to calculate the safe explosive weight per delay to be detonated in open-pit mine for the safety of multi-seams workings of underground mine. The support for the galleries and junctions were further modified for the working seams to ensure greater safety.

Jan 1, 2011