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By N Collins, A Woodley, A N. Danoucaras, C McCombe, N C. Kunz

Over the past decade, the mining industry has come to recognise the importance of water both to itself and to others. Water accounting is a formalisation of this importance that quantifies and communicates how water is used by individual sites and the industry as a whole. While there are a number of different accounting frameworks that could be used within the industry, the Minerals Council of AustraliaÆs (MCA) water accounting framework (WAF) is an industry-led approach that provides a consistent representation of mine site water interactions regardless of their operational, social or environmental context that allows for valid comparisons between sites and companies.The WAF contains definitions of off-site water sources and destinations and on-site water use, a methodology for applying the definitions, and a set of metrics to measure site performance. The WAF is comprised of two models: the input-output model, which represents the interactions between sites and their surrounding community, and the operational model, which represents on-site water interactions.Members of the MCA have recently adopted the WAFÆs input-output model to report on their external water interactions in their Australian operations, with some adopting it on a global basis. To support this adoption, there is a need for companies to better understand how to implement the WAF in their own operations. Developing a water account is non-trivial, particularly for sites unfamiliar with the WAF or for sites with the need to represent unusual features. This work describes how to build a water account for a given site using the input-output model, with an emphasis on how to represent challenging situations.CITATION:Woodley, A, Danoucaras, A N, McCombe, C, Kunz, N C and Collins, N, 2013. A robust methodological approach for mine site water accounting, in Proceedings Water in Mining 2013 , pp 335-342 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By B. Kolonja

A SIMAN and CINEMA PC-based simulation model was developed to simulate and animate the truck-shovel operations of surface mines. The model is capable of simulating one mathematical dispatching strategy using linear and dynamic programming and six heuristic dispatching strategies. Data were collected from an actual operating mine through time studies and analysis of historical records. The statistical analyses were performed and appropriate theoretical distributions were fitted for various time events in the truck-shovel work cycle. The model was then applied to study overall impact of these dispatching strategies on constrained and unconstrained mine productivity. The simulation/animation model developed in this study seems to be an efficient planning tool for choosing optimal fleets and finding an 'optimal" dispatching strategy to produce an equilibrium between "the quality and quantity of production.

Jan 1, 1993

By Jonathan Peck, Carl Hendricks

"Global Positioning Satellite (GPS) based positioning and navigation systems have been recently developed and implemented by AQUILA Mining Systems Ltd. on blast hole drills and electric cable shovels in Canadian open pit coal and iron ore mines. These systems enable the location of the drill bit or the shovel tracks to be accurately determined in three dimensions. The position of the drill or shovel is displayed to the operator via a real-time, Moving Map Display (MMD) on an LCD-VGA screen. The MMD allows the operator to accurately navigate the drill from blast hole to blast hole or maintain a desired shovel grade or face position, with respect to displayed bench features. The maps for the MMD are downloaded from the mine office via laptop or radio link as required or as mining plans change.To obtain reliable, accurate and real-time3D positions of mobile mining equipment, proven GPS technology has to be utilized. The GPS components need to operate reliably under the severe environmental conditions that exist on board mobile mining equipment. In addition, they have to contend with varying pit geometry’s and satellite configurations, with little or no performance degradation. These issues were initially examined in December1993 during a feasibility project between AQUILA and Gregg River Resources Ltd., in relation to implementing GPS systems on blast-hole drills.To achieve certain design objectives, AQUILA Mining Systems Ltd. has developed navigation systems for cable shovels and blast-hole drills based around off-the-shelf, high precision GPS components. These systems utilize the AQUILA Advanced Monitoring Platform (AMP), to display graphically, via the MMD, shovel grade and drill position to the operator to within ±12 inches of design coordinates. Production prototypes have been installed on a Marion 301 cable shovel and a Bucyrus-Erie49-R Series III drill at the Fording River Mine in August, 1995, at the Wabush Mine on a Bucyrus Erie 190-B shovel in June, 1995, and on a GD120 drill at Gregg River Resources Ltd. in January, 1996. All these systems have undergone field trials to test system components and functionality’s under actual production conditions. This paper will discuss these GPS-based positioning and navigation systems in subsequent sections."

Jan 1, 1997

By P. Fossi

This report describes a pilot-scale study of a hydrometallurgical process to treat high-grade nickel matte or a nickel-cobalt sulphide precipitate to produce high-purity electrolytic nickel. The first step of the process is the oxidative leaching of the nickel-bearing material by nitric acid; the nitrous gases generated during leaching are reconverted to nitric acid. The crude nickel sulphate nitrate solution is purified and is then subjected to a denitrification step. Nitrate separation is effected either by the crystallization of nickel sulphate or by precipitation of basic nickel carbonate. The electrolyte is prepared from the nitrate-free material and nickel is then recovered by electrolysis of the sulphate solution using insoluble anodes. Some technical and economic problems encountered with this processing route are discussed and the method is compared to the "all-chloride" process developed by Société Le Nickel.

Jan 1, 1977

By P. P. Rosario

A research project was conducted at the University of British Columbia (UBC) resulting in the development and evaluation of a novel comminution circuit incorporating autogenous grinding and parallel trains of cone crushers and high-pressure grinding rolls (HPGR). A primary driver for the circuit was to treat ore from deposits with clay and variable hardness. This paper summarizes the unique pilot-plant test program that was developed as a basis for experimental simulation and lists the main findings of the research, including the circuit?s potential operational cost savings compared to a conventional SAG circuit.

Jan 1, 2012

By K. A. Lewandowski

Heap leaching efficiency is reduced by poor solution flow characteristics (channeling and ponding), which result from compaction and fines migration. Agglomeration of the ore can prevent compaction and immobilize fines, but copper leaching requires an acid-resistant binder to stabilize the agglomerates. Until now, there has not been a satisfactory way to evaluate whether a binder was effective, other than squeezing a handful to see if it ?feels right.? Procedures have been developed to quantitatively determine whether a binder produces agglomerates that can withstand compaction in an acidic solution, and have identified several binders that will provide sufficiently compaction-resistant agglomerates for copper heap leaching. Keywords: Copper heap leaching, Binder performance, Compaction

Jan 1, 2010

By D Kentwell

A resource model serves two main purposes depending on the stage of a project. The first is to provide an early indication of likely tonnages and grades at certain cut-offs so that decisions can be made on whether continued spending on the project is justified. The second is to provide a basis for mine planning, feasibility studies and reserves. Resource models are not designed for selection of actual blocks in the ground for processing. This is the purpose of a grade control model, which is created at a stage beyond both resources and reserves.Inferred, Indicated and Measured Resources contain different levels of uncertainty with respect to the accuracy of the resulting grade and tonnage curves. These uncertainties arise from three broad areas: quality of information, geological assumptions and estimation technique. This paper focuses on known problems with the ordinary kriging (OK) estimation technique. Resource estimates often produce smoothed block grade distributions with much lower block grade variability than true selective mining unit (SMU) block grade distributions. There are two main factors that are involved in this smoothing. Firstly, where the block size used for estimation is larger than the SMU block size, this will smooth the block grade distribution and move the grade and tonnage curves away from the true SMU block grade and tonnage curves. Secondly, and less well recognised, is that smoothing is inherent in the OK estimator. This also moves the grade and tonnage curves away from the true SMU grade and tonnage curves, even when the estimate is done at the SMU block size. There are a number of techniques, such as simulation, uniform conditioning and degraded search neighbourhoods that can provide a better approximation of the true SMU block grade and tonnage curves at the expense of individual block accuracy.This paper aims to explore the extent to which OK resource estimates designed to maximise individual block accuracy can differ from (an estimate of) the true resource at SMU block size in terms of grade and tonnage curves. The differences at economic cut-offs and above are examined. In some cases these differences are significant. Both the OK estimation technique and block size play a part in the differences observed. To do this we will examine a number of commodities and deposit types using real project data.The conclusion is that the current industry standard default practice of targeting maximum individual block accuracy (conditional unbiasedness) using OK at resource stage, without consideration or evaluation of the extent of associated smoothing at SMU scale, can lead to significant errors in fundamental mine planning decisions. This then has implications for resource classification if the classifications are based heavily on the OK quality without consideration of the true SMU distribution.CITATION:Kentwell, D, 2014. Aligning resource estimates with mine planning, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 185–192 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By J. B. Morrow

Methods of Coal Preparation Fundamentally, the object of coal preparation is to increase, economically, the value of a fuel by making it more suitable to the uses of the consumer. This can be accomplished in three major ways: 1.Screening or sizing 2.-Mixrng or blending 3.-Cleaning By combinations of any or all of these methods we can prepare coal to meet standard specifications-a process of standardization which is the more desirable the more nearly it approaches the unvarying quality of packaged goods, where the package you buy today and tomorrow is the same as that you bought yesterday. It should be noted that it is readily possible to get good cleaning and still have poor preparation because of faulty screening and mixing, and, on the other hand, it is possible to get a passable grade of cleaning, combined with good screening and mixing facilities.

Jan 1, 1931

By M Recabarren, A Echeverria, J Ronda, J I. Guzman, R Dodds, G Juarez, E Vila-Echague

A strategic mine plan is a fundamental part of any mining operation. It must provide a realistic and operative extraction and processing schedule, and yield the highest value for the business. For open pit mines, the problem can be modelled as a set of blocks representing the deposit, for each of which we need to decide if it is going to be mined, if so, when and where it will be sent (process, stock or dump).This problem can be proven to be of NP-Hard complexity. The traditional approach used by mining engineers to tackle this complexity is to separate the problem into more tractable components, solving each separately. The first step is to use the Lerchs-Grossman (LG) algorithm to obtain the final pit limit, as well as a set of optimised pit shells (nested pits), using different input prices. Then, using this input, operational phases are designed. Third, the set of phases can be used as an input for a phase-bench style optimisation, usually using a mathematical programming-based algorithm.There are, however, several problems with this approach. First, dividing the problem into simpler parts has the consequence that any compromises made at early stages limit the potential value left for the following steps. Second, LG is a static algorithm, with no concept of the time-value of money, capacity limits, opportunity costs, etc. Phase design is essentially a manual step, for which nested pits provide insufficient information in practice, and therefore the quality of the result in terms of potential net present value (NPV) depends strongly on the experience and expertise of the designer. This means that key input data such as commodity prices, different processes capacities and mine movement limits, are considered only at scheduling, when there is little room for optimisation. This sequential approach limits the potential value in each step, where a simplified problem is addressed, instead of addressing the real, and more complex problem, which is dynamic and should be solved as a whole.We present in this paper an algorithm, and its commercial software implementation, that addresses the dynamic problem as a whole, simultaneously and automatically creating a high-value strategic mine plan that adheres to basic operational constraints, determining dynamic cut-off grades and delivering a set of phases which can serve as a much stronger guide than nested pits for the final design. We discuss some of the key elements of the algorithm and propose a new methodology for strategic mine planning, where phase design dynamically responds to mining strategy definition. Results using different mining and operational parameters on a fictitious copper deposit are used as a demonstrative example.CITATION:Juarez, G, Dodds, R, Echeverria, A, Guzman, J I, Recabarren, M, Ronda, J and Vila-Echague, E, 2014. Open pit strategic mine planning with automatic phase generation, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 147–154 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By A. K. Martin

Adaptive management can be described as a structured, iterative process of robust decision making in the face of uncertainty, with a goal of reducing uncertainty over time through system monitoring. Adaptive management is a tool which can be applied to not only change a system, but learn about the system (Holling, 1978). Adaptive management has been used in ecosystem management for years and guidance is provided in a variety of handbooks and publications. Adaptive management can be applied to industrial facilities and mines through the use of an adaptive environmental management plan (AEMP) and associated practices. The goal of this paper is to provide an explanation of how the plans and practices support regulatory agency approvals and permitting, span the life-cycle of mines, manage uncertainty, and assist in addressing mining impact and legacy issues. AEMPs and associated practices are useful tools to address the uncertainties in identifying, evaluating, and managing impacts of proposed new and modified mining facilities undergoing environmental review. Once a proposed project is approved, the AEMP continues as a living document, being informed, revised, and adapted by the operations. The AEMP can serve as an ongoing management tool for describing and evaluating environmental impacts, continuing in operations into post reclamation. If initiated during planning and environmental review of a project (and in some locations such as the United States [U.S.], the preparation of an Environmental Impact Statement (EIS)), the AEMP becomes a basis to identify, monitor, and manage potential project environmental impacts. Development of an AEMP for an operating mine is also beneficial since there are generally developing and ongoing environmental issues at those facilities as well. Over time, the AEMP is adapted to changing requirements and conditions including those anticipated and unanticipated. Ever increasing scrutiny of mining projects and the complexities of the EIS process highlight the uncertainties inherent in impact predictions. In making the momentous decision of initial project approval, these uncertainties can discourage the regulatory agencies? actions and create stakeholder anxiety and controversy about a project. A well-designed AEMP can support the decision to approve an EIS and enable a project to move forward. Additionally, an AEMP can inform financial assurance estimates and revisions over the life of a mine providing all parties including the citizens of the surrounding communities with greater confidence that potential environmental impacts and risks will be well managed.

Feb 23, 2014

By Raymond T. Moore

The Federal Coal Mine Health and Safety Act of 1969 (FCMHSA) begins with this statement: "Congress declares that the first priority and concern of all in the coal mining industry must be the health and safety of its most precious resource -- the miner; . . ." At the Federal level this responsibility is shared by the Department of the Interior and the Department of HEW. The health research and standard setting activities under the Act are largely the responsibility of the Department of HEW, and with the exception of Title 4, Black Lung Benefits, have been delegated to our Institute, which I will refer to henceforth as NIOSH. In addition, we bear certain joint responsibilities with the Department of the Interior. These include dust sampling and respirator approval. To complete the picture, the Department of Labor has recently assumed Black Lung Benefit respon¬sibilities from the Social Security Administration under Title 4 of the Act.

Jan 1, 1974

By Gary E. Slagel

The federal Office of Surface Mining (OSW) has undertaken an effort to revise many of their permanent program regulations. Numerous procedures for compliance are being rewritten to allow for greater flexibility while meeting the requirements of the Surface Mining Control and Reclamation Act. This study investigates, for certain select provisions, the cost differential between complying with the original OSM standards and the more flexible, state-specific standards being allowed in many of the revised regulations. Estimated cost savings that could be realized under a few of the revised regulations are substantial and should provide a basis for seeking revisions to the state regulatory programs.

Jan 1, 1982

By Mike Fontaine

The success of a project is defined by meeting the financial performance objectives of the business case within a stipulated timeframe. Early in design, little information is normally available; the uncertainty introduces risk to the project outcome. Using a range of risk management tools and techniques, a project can be developed from front end loading phases 1 through 3 (FEL1–FEL3), and project implementation (FEL4) and then into operations with an optimized probability of success. For every project element, the risk management framework embodies: establishing a context; assessing risk (identify, analyze, and evaluate); and treating risk. Embedded within design activities, this process mitigates or eliminates risks. Monitoring and control, as well as extensive communication and consultation with stakeholders, is integral to the risk management process.

Jan 1, 2015

By Marline J. Veesaert

Urban quarries offer one of the greatest opportunities for profit in non-metallic mining with limited financial risk IF properly evaluated, planned and developed to meet market needs. Location, with respect to market, is the prime consideration. Geologic considerations and quality of rock are nearly as important. Cost factors and return on investment (ROI) are the principal financial considerations. Risk of capital is determined by weighing all factors that should be considered and how well judgements are based on information acquired. It is a simple, true axiom of business that an investment must be founded on amount of capital required with its expected return plus profit, expertise required to operate and time involved. Urban quarries generally offer excellent stone product market opportunities. Costs of land with mineral containment and processing operations are much greater than in rural areas. Environmental problems have become increasingly severe. Competition from other quarries in the market area is usually directly proportional to the profit attractiveness. Risk of capital (initial, developmental and operational) can be evaluated and reduced only by thorough analysis of the entire situation. Time and money expended on planning and preliminary investigations probably represent the most productive investment of available company resources.

Jan 1, 1977

By G. Favini

A Bayesian decision model of minimun risk, based on the probability and costs of mine discoveries and non-economic projects, is presented for massive sulphide exploration in the Canadian Shield. The sample used for the model is composed of data relating to forty mines, sixty non-economic sulphide occurrences, and sixty occurrences of graphitic and pyritic material. These economic and barren samples consist of drill-tested occurrences which were, in varying degree, characterized by conductivity anomalies. Given the large size, the reliability and the homogeneity of the data base available for massive sulphide exploration, it is shown that certain statistical models can and should be utilized as a tool for decision-making by explorationists. Given this data base, information theory tells us that only those signals that are independent of one another will transmit information with minimum error. An ensemble of six significant multilevel signals, markedly independent of one another and consisting of numeric and geometric form descriptions derived from Bouguer anomaly, aeromagnetic and physiographic maps, were identified and evaluated by case studies. The use of these signals as input in a simple statistical procedure, or in a carefully planned and experienced visual appreciation scheme, can be of significant aid in decisions concerning the choice of favourable areas or sectors to explore in detail. The method of discriminant analysis is theoretically and practically suited for the statistical modelling involved. By way of a simulation on our statistical model, the efficiency of the model and of the underlying criteria is determined for historic cases and, by inference, for its validity in future exploration. An approximate optimized solution is derived from the model which suggests that over 90% of the known ore could be found by screening, according to a model such as that herein described, and drilling only 30% of the targets (mostly barren) normally identified and tested in current and past exploration.

Jan 1, 1979

By B. W. Lawrence

Shaft alignment requirements are consistently met using conventional shaft sinking methods. Little attention has been given to achieving similar alignment accuracies using rotary drilled shaft methods. Alignment of these shafts is difficult to control and guarantee. Bare shafts and shafts that use drum hoisting systems can accept some deviation. However, combining drilled shafts with Koepe hoist installations presents new accuracy requirements for drilled shafts. This paper describes the importance of verticality with practical examples, and discusses various methods of measuring verticality and their respective limitations.

Jan 1, 1989

By A. R. Laplante

A novel methodology to estimate gold recovery by gravity is presented. The methodology makes use of a population balance model which represents gold liberation, breakage and classification behaviour and applies pre-concentration and recovery performance curves to gravity-recoverable gold to predict overall recovery. Derivation of the necessary parameters is explained and demonstrated using data from an actual gravity circuit and one projected application. The methodology makes it possible to estimate the performance of circuits with large gold circulating loads and relatively low unit recoveries (e.g. jigs), or with high recoveries on a bleed of the circulating load (e.g. Knelson concentrators).

Jan 1, 1994

By W. E. MacDonald

This paper relates the story of 100 years of mining in the Harbour Seam at the Princess Colliery, Sydney Mines, Nova Scotia. Several interesting anecdotes are included along with the discussion of the evolution of coal mining methods in the area. Finally, some of the recently introduced equipment at Princess Colliery is described, and prospects for the future of the industry are outlined.

Jan 1, 1968

By E M. Gama, L Resende

The tailings are waste from mineral processing operations. The type of tailings of iron ore processing are classified into sandy tailings and mud. Already the overburden are showing significant levels of useful mineral. Both iron ore`s waste have in your composition phyllosilicates/clay that indicates the potential for use in niche markets as paving and cement. According to several studies, there are various technologies in bench and pilot levels that could be used on a large scale but there is not an economic environment, tax, regulatory and tax set. Many of these technologies are associated with the reuse of tailings and overburden in construction. All these factors influence for that so many initiatives remain in search formats and cannot advance to the new business format. There is no way to set goals of reuse of this waste, as already occurs in China, if there is not a fiscal, tax and economic structure to support such measures. The way to foster and ensure that reuse of tailings and overburden is an incentive for promoting a culture of circular economy that would allow the emergence of an ecosystem between the private, public and Government sectors with the objective of accelerating and subsidize the entire network of reuse of this waste. The closure of the mine could be the tool used to ensure and boost this ecosystem of reutilization to align it with the vocation of the area of the mining law. Following this model, the end of the mining activity could provide a financial return to the local population, a more effective environmental compensation and a reduction in costs related to the closure of the mine. In this study are shown how the Vale is working in the reuse of tailings and overburden.CITATION:Resende, L and Gama, E M, 2018. The challenges of the reuse of tailings and overburden, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 117–125 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By J. B. Mawdsley

A LITILE north of the geographic centre of the Province of Saskatchewan, 150 miles north of the city of Prince Albert, is a narrow green-stone and sedimentary belt of pronounced structural characteristics. This belt, generally known as the Sulphide Lake belt, is about two and a half miles wide. During the past three years prospecting has uncovered numerous gold-bearing showings occurring chiefly along the centre of the belt for a distance of at least nine miles. The number of these showings, the nature of some of them, and their relationship to strong structural features, make it altogether likely that intensive work will eventually locate ore-bodies that will be of economic importance. The discovery of gold in the fall of 1938 on the south shore of Mackay lake, about five miles northwest of the Sulphide Lake gold-bearing belt, indicates that there are neighbouring zones of interest. This paper, an attempt to outline the present status of the interesting mineralized belt, is based largely on the information gained on a five-day tour of this district, made in August, 1939, on behalf of the Department of Natural Resources of the Province of Saskatchewan. The Sulphide Lake belt is named after a small lake centrally located in it. This lake and others are just north and within short portage distances of some of the long bays along the north shore of Lac La-Ronge, an irregular, island-studded lake, about twenty miles in diameter, in relatively rocky Precambrian country, just north of the Palaeozoic contact. The fur-trading post and settlement of Lac La-Ronge is on the west shore of this lake and a road, now under construction, will shortly link this community with the city of Prince Albert. In the past, the most direct route was an indifferent canoe route, in part following Montreal lake and river; more recently, the aeroplane has made this section easily accessible.

Jan 1, 1940