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By J. F. K. Brown

WHEN I first received the kind invitation extended to me by the Mining Society of Nova Scotia, I read over very carefully the suggested title-"The importance of long-distance planning and budgetting in modern methods of mining, and the advisability of working to some definite plan". I came to the conclusion that I might as well confess my inability to handle properly such a vast and intricate subject within the scope of any one paper. More properly, I think a round-table discussion should be indulged in-a sort' of symposium carried on in similar fashion to the World Power and Coal Conferences- you know, a committee for this, a committee for that, and, finally, a committee to see what the committees are doing. Weil, your Secretary's suggestion is just like that- much too comprehensive for any half-hour's presentation. As a paper, also, it either becomes too general and therefore uninteresting, or i.t descends into detail and describes means and methods to the end desired, which have little attraction because they were designed to meet quite different conditions than those my audience would mentally be considering. Of the two evils facing me, I have chosen the one that sticks to the generalities. Your Secretary's query almost automatically divides itself into two distinct phases: First, the importance, and second, the advisability, of planning. Let us dwell for the moment on the second, because, if we can prove advisability, that leads to desirability and, finally, to doing. Proving is the difficult part of the little problem. Here was something I, personally and as a mining engineer, had been battling for all my corporate life without being able to prove it to anybody. Then I saw the way out of that. I perceived I could put that little question of advisability on another basis altogether-:put it in the class of "coming- some day- soon" whether you or l or anybody else liked it or not; call it, if you please, mandatory, certain, necessary, enforceable planning. All of which means that the problem of advisability has rather suddenly become the very practical one of "how to do it". Why?

Jan 1, 1937

By L J. de Lange

As a material asset for mining entities, the resources and reserves (RR) estimation processes are surprisingly underrepresented in the assurance landscape. When press reports expose them being inaccurately reported, or in merger and acquisitions processes, their importance becomes clear. The impact of erroneous RR numbers (both positive and negative) could have a material impact on an entity’s reputation and value.The technical nature and ‘black magic’ connotations of the RR estimation processes are possibly reasons why audit committees are not actively involved with it. Internal auditors avoid the RR processes for similar reasons. Also the traditional approach to obtain assurance on RR is expensive and is therefore only performed when it is absolutely required.However, stakeholders’ expectations of good governance are growing. Part of this increased focus is based on attaining a higher degree of certainty about the current and forecasted position of the entity. Stakeholders are also increasingly more interested in non-financial areas of entities, as the future success of an entity is more than a set of financial metrics.Consequently, the RR estimation processes should be visible on the agendas of audit committees. Monitoring of key controls is required as part of the governance obligations for senior management and the audit committee. So once it is on the audit committee’s agenda, the question then becomes, how will that agenda be supported by an assurance process that is cost-effective?The main objective of the paper is to describe a model of RR assurance that has been effectively applied in some mining companies. The paper discusses one particular approach that provides an audit committee with the required assurance regarding RR processes. The approach ties the assurance needs of the audit committee to the needs of the technical experts in the entity, therefore involving two important figures. It also offers assurance providers with a model to audit ‘through’ the RR processes rather than ‘around’ them. The paper then discusses top-down and bottom-up approaches that provide assurance at different levels of an entity.A governance audit that focuses on the RR processes is suggested as a top-down approach. A bottom-up approach assesses the design adequacy of internal control processes. A hybrid model is described which meets the needs of diverse stakeholders including the audit committee and the RR community.The hybrid model combines the expertise of professionals in both internal audit and RR. The right balance of these skills directed by a singular approach ensures that a credible result is achieved.This approach is not as expensive as some verification approaches used in the industry and can, as a result, be performed on a more regular basis.The last element of the paper looks at implementation of the reporting mechanism. An assurance process aimed at continuous improvement further enhances the robustness and reliability of RR reported by an entity.CITATION:de Lange, L J, 2016. Resources and reserve assurance processes – a framework for improved governance, in Proceedings International Mine Management Conference, pp 21-34 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 22, 2016

By K Fiedler, A Newell, P D. Munro

Test work is the foundation upon which the success of projects and subsequent operations is laid, reflected in Professor Arthur Taggart’s pithy observation: ‘Make your mistakes on the small scale and your profits on the larger scale’. Indeed, Professor AllanTrench has succinctly noted that ‘Get the metallurgical characteristics wrong and you don’t have a project’.With deposits becoming lower grade, more structurally and mineralogically complex, final products requiring lower levels of impurities and tailings management demanding more attention, test work now assumes even greater significance in the acceptance and successful execution of a project. This paper is the first in a series aiming to stimulate thought on the metallurgical test work process by getting back to the fundamental basics through exploring and providing some guidelines for the metallurgical testing world, noting preferred practices as well as precautions and mitigations. This covers the key characteristics of metallurgical test work programs, including what needs to be done, sample selection, quality control and associated drivers, and most importantly, selecting, assessing and managing test work facilities. CITATION:Newell, A, Munro, P D and Fiedler, K, 2018. Metallurgical test work – between a rock and a hard place, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 15–32 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By Charles Vaught, Richard S. Fowkes, Ronald S. Conti, Barbara Fotta, William J. Wiehagen

The purpose of this study was to determine mine workers' state of fire-fighting preparedness and the technology being used to detect and respond to underground coal mine fires. To investigate this problem, 214 underground coal miners were interviewed by U.S. Bureau of Mines researchers. Frequency distributions of workers ' responses are presented in this report, along with segments of narrative accounts, to profile miners' fire-fighting capabilities. The data indicated that much variability exists from mine to mine and that there are several important changes operators may undertake in order to make miners better prepared to deal with fire underground: select appropriate sensors, establish and test a warning and communication protocol, construct a system capable of delivering hundreds of gallons of water per minute for sustained periods, institute formal fire preparedness audits, develop case studies of events that occur at an operation to use as teaching and assessment tools, and provide structured practice that can be incorporated into fire drills.

Jan 1, 1995

SACPE has asked the Journal to bring the following points to the notice of members who are about register with SACPE. When to Apply There is no set time to apply for registration. Engineers should apply when they believe that their training has met all the requirements of Policy Statement No. 1/3. Pitfalls Remember that it is the applicants' training that must be evaluated, and this requires the avoidance in the application of vague generalities such as 'My duties were design plant including its economic evaluation' or 'I was engaged in . . Requirements An example of what is required can perhaps best illustrate the point.

Jan 1, 1982

By Z. T. Bieniawski

After many significant advances in mining including development of sophisticated methods for strata characterization and numerical modeling analyses, the engineering design process in mining is as primitive as it was two decades ago. Yet, major advances in design methodologies have occurred in other branches of engineering. Is creative design in mining a myth only? Are we deluding ourselves when we talk about innovative mining design of today? What is the reality of the situation? This paper explores the methodology of creative engineering design as a new recognized discipline. It warrants applications in mining since design experts are sometimes unaware of their own decision-making processes.

Jan 1, 1988

By M. F. Vancas

Control of the interface elevation between the aqueous and the organic phases in typical settlers is a fairly straight forward principle. However, when looking at the details involved in actually designing the aqueous and organic discharge launders and weirs, one comes to realize just how sensitive the system is to small variations in operating conditions and/or parameters. This discussion focuses on the details that must be considered during design, looks at the various types of control systems typically used (from the basic manual systems through to full automation), and equally importantly, looks at what happens in an operating plant when the conditions and/or operating parameters change.

Jan 1, 2007

By John Austin, Graham Pingram

The idea of GOLD 100, an international conference on gold, was first conceived by Mr Les Haughton of Mintek in mid 1984. By the beginning of 1985, plans were well advanced to hold what was to be the most comprehensive conference on gold ever organized. Appropriately, GOLD 100 was timed to coincide with the celebration of Johannesburg's centenary. Leaching The South African Institute of Mining and Metallurgy will hold a two-day colloquium on the topic of leaching on 8th and 9th November, 1988, with the objective of bringing the latest developments in leaching technology to the attention of the mineral-processing industry.

Jan 1, 1988

By K. M. Atencio, T. Pike, S. Forrest

We will introduce the Small Business Liability Relief and Brownfields Revitalization Act, which is an amendment to CERCLA and the types of sites it includes and excludes, especially as related to mine-scarred land. We will also describe the types of available funds, whether they are competitive or not, what entities are eligible to receive them, and how to access them. We will introduce the legislation’s liability provisions; for example, the recently issued interim guidance clarifying some of the conditions that contiguous property owners, bona fide prospective purchasers, or innocent landowners must meet to qualify for the liability limitations provided in the Brownfields Law.

Jan 1, 2004

By P. G. Semple, K. W. Major, P. Eng.

The recent increase in development of refractory gold deposits has resulted in changes to the traditional treatment processes. The selection of the preferred refractory treatment process is dependent on the mineralogy of the ore. One process, which has recently gained increasing attention, utilizes dry grinding and roasting of the whole ore. This paper will discuss some of the considerations to be addressed during the design of the process fl owsheet and what the effects of the various alternatives will be on the plant capital and operating costs. The paper will be based, in part, on current experiences with dry grinding, roasting plant design and start-up.

Jan 1, 1990

By D. H. Davidson

In situ leaching (ISL) of copper has the potential of reducing both capital and operating costs for copper production. The ISL process combines surface facility (SX/EW) and wellfield operations, each of which must process the same total flow rate and pregnant liquor copper concentration. Commercial cost data are only available for SX/EW facilities. This paper discusses: the interaction between the principal wellfield costs associated with well modules, and wellfield start?up with SX/EW costs; how to estimate what the level of wellfield costs must be to optimize DCF/ROR; and how to relate these wellfield costs to orebody geologic and mineralogic characteristics.

Jan 1, 1988

By Dale C. Matthews

Pressure oxidation of refractory gold ores is becoming more popular in what has become an environmentally sensitive society. This article discusses some specific process problems and solutions involved with starting up and operating an autoclave circuit. The Getchell gold deposit is located about 72 km (45 miles) northeast of Winnemucca, NV. The deposit was discovered in 1934 and first production came about in 1938. The oxide portion of the ore body was mined and milled from about 1936 through 1950. Refractory arsenic-bearing sulfide ores had long been known to exist in the Getchell deposit. These ores had been mined concurrently with the oxides since 1938.

Jan 1, 1991

The Howe Memorial Lecture, in memory of Henry Marion Howe, Past President of the Institute, was authorized in April, 1923, as an annual address to be delivered by invitation under the auspices of the Institute by an individual of recognized and outstanding attainment in the science and practice of iron and steel metallurgy or metallography, chosen by the Board of Directors upon recommendation of the Iron and Steel Division. The following were the Howe lectures and lecturers for the years indicated: 1924 What is Steel? By Albert Sauveur. 1925 Austenite and Austenitic Steels. By John A. Mathews. 1926 Twenty-five Years of Metallography. By William Campbell.

Jan 1, 1940

STANFORD UNIVERSITY, CALIFORNIA Our activities for the year 1918-19 have closed with the coming of summer. It has been a most successful year in many respects, especially in the reorganization necessary after the war conditions had passed. An INITIATION SCENE AT STANFORD UNIVERSITY. "old-days" initiation was held on the Stanford campus by the Society a few weeks ago. The accompanying picture explains some of what took place when the following men were taken into the membership: W. P. Winham, Salinas, Calif. ; T. L. Wark, Long Beach, Calif.; P. L. Henderson, Greeley, Colo.; T. E. Bassett, Palo Alto, Calif.; and R. G. Wheelton, Long Beach, Calif. CHAS. A. DOBBEL, Secretary.

Jan 8, 1919

The perennial challenge facing mining and minerals operators is to improve productivity, usually by a combination of cost reduction and performance improvement. In a typical production situation involving mining and processing activities, the standard approach has long been to seek improvements in each activity, effectively in isolation from each other. However, the realisation is growing that there is considerable potential to achieve really substantial productivity gains by much improved integration of mining and processing with the key being to consider what is best in the total sense. Some of the linkages between fragmentation in mining and downstream processing are considered in this paper. These linkages involve technical, operational and economic Considerations.

Jan 1, 1997

A universal grinding circuit model suitable for an arbitrary structure of flowsheet has been suggested. In this model classifiers and mills are described in a most general form. What puts the model in a class by itself is the automatic mass balancing in all streams of the circuit. In order to provide this a special classifier model is adopted. A previously published continuous steady state process model is used as a grinding model. Non-linearity of classifier model leads to a resultant circuit model which is equivalent to a non-linear integral equation. It complicates somewhat calculation algorithm in comparison to that of linear model, but provides a physically meaningful solution.

Jan 1, 1993

H. F. MOORE and W. J. PUTNAM (author's reply to discussion?).-The writers are inclined to question whether it has been experimentally established that steels will endure an indefinite number of repetitions of low range of stress. It is difficult to see how such a conclusion can be reached except by extrapolation from test data,. and such extrapolation always gives results of questionable value. From the viewpoint of the designer and the user of steel the writers believe that the exponential formula, which gives results on the safe side of what test. data we have, for steel subjected to tens or hundreds of millions of repetitions is a safer

Jan 7, 1919

By Fredrick C. Kruger

Risk capital for mining ventures becomes harder to get each year as the costs for exploration, construction and money continue to skyrocket in today's inflationary economy. Because of this and because mining prospects must compete for the same dollar as many other needs of a diversified company, then the success or failure of any new proposal depends on how well its return on investment compares with all other capital requests. Mr. Kruger presents case histories showing what it costs to explore for new mines, how many of these prospects reward their promoters with success and how well some of the more famous mines have paid off.

Jan 9, 1969

By John J. Theiler

Early in 1963, the Inspiration Consolidated Copper Co., at Inspiration, Ariz., began a program to make automatic the lubrication of several critical points on their KW Dart 37SL haulage trucks. Prior to installation of the automatic lubrication system, all the haulage trucks were serviced by hand every three shifts. Now, with automatic lubrication, the service period has been extended to four shifts. What are the principal benefits to be expected from such a system? 1) Uninterrupted production; 2) extended machinery life; 3) good housekeeping; 4) lower maintenance costs. Of these points, the most important to truck maintenance are extended component life and lower maintenance costs.

Jan 5, 1965

By Bruce T. Stanley

A key point in the design and operation of a modern mining operation is the construction of what is called an ore-body model or block model. This model is a representation of reality constructed from predicted information. The blocks involved are merely subsets of the overall model which allows manipulation of the contained information on a local scale. In general, block models enable mine planners to effectively select the most promising means of extracting the ore both physically and economically. The uses of a block model can be quite diversified, but one must realize that a single model that satisfies all curiosities and forms of expertise is difficult to construct.

Jan 1, 1979