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By Noble AC

Ore reserve reporting practices in the United States may be broken into four general categories as follows: ò Reserve reports, often of an unofficial and preliminary nature, which are made through the news media. These are often based on exploratory drilling or sampling results. ò Reserve reports made for the purpose of raising public funds by issuing securities on the stock market, or as part of other filings to the United States Securities and Exchange Commission. ò Reserve reports to obtain private funds from banks, financial institutions, or other investors. ò Reserve reports for internal use and planning by companies operating or evaluating mineral properties. This paper discusses current practices for each of these types of ore reserves reports and reviews recent changes which have affected those practices.

Jan 1, 1987

The Professional Standards Act responds to the growing problem of professional liability by introducing a mechanism whereby professional associations can have schemes approved. Those schemes include a cap on liability; a requirement for compulsory insurance; the development of risk management strategies; and the establishment of a complaints and disciplinary system. The Act is also designed to support and develop the concept of self-regulation by the members of occupational associations who provide services to the community by providing them with those tools. It implicitly accepts that self-regulation is preferable to statutory regulation and that self-regulation serves the interest of the community and of the providers of services. The Act arose from a review of professional liability commenced in 1988. The Attorney General's Department produced an Issues Paper, released in September 1989, which outlined in detail the extent of the problem. This was widely circulated and an extensive number of comment were received.

Jan 1, 1995

A proved routine mapping practice is described involving detailed observations on grade and structure. The equipment and methods employed are giving good service under the conditions encountered. Stopes are mapped on every floor whether timbered or open, "Kodatrace" workplans and sections being used, and in addition all development whether in country or lode is mapped.INTRODUCTIONThe accumulation of geological data for application to current mining problems and to the search for new ore involves the necessity for close mapping of all available underground faces and backs. The technique which has been developed to suit conditions at the North and British mines of North Broken Hill Limited forms the subject of...

Jan 1, 1940

By A Crosky, S Saydam, H Chen, H L. Ramandi

Cable bolts and rock bolts are used as primary and secondary anchoring systems in many underground mines. Reports on the premature failure of cable bolts and rock bolts due to stress corrosion cracking (SCC) in underground coalmines have been increasing in the past two decades. The previous studies found that the SCC in both rock bolts and cable bolts occur as a consequence of atomic hydrogen diffusion into the material, which is known as hydrogen-induced stress corrosion cracking, HISCC (Craig et al, 2016; Wu et al, 2018b). While research to understand the process of SCC occurrence in underground mines is still required, finding a prevention solution to protect the bolts from HISCC is crucial. In this study, we analyse a variety of commercially available coatings for steel corrosion prevention, including barrier coating (ie epoxy, polyester TGIC) and sacrificial coating (hot-dip galvanising). We test the coating on coupons manufactured from rock bolts and cable bolts used in the coal mining industry.

Nov 29, 2022

By S Mundell, A Atkins, S van de Water

Geoscientific information management enables the capture, management and delivery of the original geoscientific observations and measurements of the earth’s natural resources. However, original observations and measurements are worth nothing if the quality and integrity of the data can’t be guaranteed. Geoscientific information is one of the fundamental assets enabling miners to make confident and accurate business decisions, whether that is defining a resource model, performing reconciliation, delivering ore reserve reports or meeting environmental compliance requirements. Without access to reliable, validated or verified data it increases the risk of miners using incorrect information for reporting and compliance. Industry codes, such as JORC, or government regulations, such as environmental compliance requirements, must be adhered to and companies should be able to confidently report to these standards. Without having a robust information management framework in place, it becomes a challenge to make trustworthy decisions, report confidently and reduce the risk of non-compliance. As a key initiative, good data governance should form one part of a miner’s information management strategy. Within the mining industry it is common for companies to only consider technology tools as the key focus for compliance whereas a mature information management focus will additionally consider people and process. All three pillars are critical for a miner to have confidence in their data driven decisions. This paper discusses an industry framework for best-practice geoscientific information management based on the observations gathered from analysing data management practices within the mining industry. It focuses on how the three pillars of people, process and technology are crucial elements to improve operational decisions and ensure companies are compliant.

Nov 8, 2021

By M Hawkes, Z Ji Gang, Z Ming, R Hassell

As underground mines become more geotechnically challenging with increasing depth and excavation size, the requirement for ground support to be installed as per design becomes more critical. The verification of installation quality for cable bolts and grouted rock bolts is difficult to assess. Current methods to control quality have limitations; pull testing is largely inconclusive with only extremely poor installation being identifiable. Audits during installation can only capture a small percentage of installed bolts. Following large rock mass displacement from either squeezing ground or seismic events, even previously well installed bolts may have yielded and require replacement. A method to provide an improved understanding of the reinforcement installation quality is Non- Destructive Testing (NDT) using acoustic reflection. To validate the accuracy of an NDT system, both plain and bulbed strand cable bolts were grouted in clear plastic tubes. The encapsulation grout quality was deliberately varied from full encapsulation through to partial encapsulation and a range of different size voids. The clear tubes allowed the ground encapsulation to be observed. Cable bolts strands were cut at varying lengths and different water cement grout ratios were used. Acoustic testing of the cable bolt specimens was completed blind; the technicians were not aware of what was being tested. The NDT results correlated well with the grout encapsulation, with differences between full encapsulation, minor voids and major voids being determined. The different water cement ratio and bolt lengths (including when partially cut) were also identifiable but with some discrepancies. Trials of the technology underground have also shown the data collection process to be relatively quick with each bolt taking 1-2 minutes to test, with interpretation of the results able to be completed soon after. The NDT results collected from the underground trial showed a wide variance in cable bolt grout encapsulation quality indicating that there were installation issues.

Mar 15, 2021

The paper describes some of the economic and human factors associated with haulroads on Mount Whaleback, a large open pit iron ore mine. These factors have combined to encourage formation of a specialised road maintenance crew which caters for haulroad construction and maintenance. Techniques used for design, construction, operation and management of haulroads are then described. Future developments are expected to effectively lower construction costs leading to an even wider application of the techniques described and consequent improvement in temp- orary roads and overall truck performance. INTRODUCTION Mount Whaleback is a large truck/shovel open pit iron ore mine located in the Pilbara region of north Western Australia. Annual production capacity exceeds 100 million tonnes per annum of waste and ore. The truck haulage fleet comprises WABCO 120 52 WABCO 3200 22 74 of which approximately 45 are operating at one time.

Jan 1, 1982

By Kurzeme M, Willoughby D. R

The current approach to the design of fill, as a structural component in a mining system, is based on traditional usage, previous experience, empirical rules and preconceived ideas. This approach does not permit the relative economicsof the various possibilities to be evaluated, retards introduction of new materials or processes, and results in fragmented fill research effort.A rational approach to the design of fill is proposed as a means of overcoming these disadvantages.This is based on five components:(a) statement of functions of fill,(b) definition of modes of fill response,(c) criteria of satisfactory performance,(d) analysis of fill response,(e) specification of required fill properties and methods of obtaining them.An assessment of each component indicates that the adoption of this rational design approach will require research effort in categorising modes of fill response and in defining criteria of satisfactory performance.

Jan 1, 1973

The weathering of different types of base metal deposits in the semi-arid environment of the Lachlan Fold Belt of western New South Wales affects the geochemistry of outcropping ironstones (gossans) and derived soils. W eathering of the pyrite- and pyrrhotite-rich mineralisation at the Elura Zn-Pb-Ag deposit leads to highly acidic conditions and strong depletion of Cd and Zn throughout the profile. There are local attainments of high concentrations of Ag, As, Ba, Cu, Hg, Pb, Sb and Sn in the profile and As, Ba, Pb and Sb are still highly anomalous in surficial material (ironstone and soil). However, at Parkers Hill, in the Mineral Hill Field, the primary Zn-Pb mineralisation is pyrite-poor and so weathering is not as acidic as at Elura. Thus, although Ag, As, Cd, Cu, Sb and Zn may be concentrated at various levels in the Parkers Hill weathering profile, Cu and Zn (as well as As, Pb and Sb) are retained in surficial ironstones in essentially the same abundances as in primary mineralisation. Thus, variations in the suite of geochemical indicators present in ironstones and residual soils are likely to reflect differences in the original mineralogy and the degree of acidity produced during the weathering of base metal mineralisation. Hence, an understanding of weathering processes is necessary to fully interpret exploration geochemical data.

Jan 1, 2004

Using a new type of laser surveying instrument named Particle Dynamics Analyser (PDA), the distributions of the radial and axial components of the mean velocity, the size and the concentration of solid particles at selected positions within a transparent hydrocyclone were directly measured out for the first time, from which profiles of the flow field of solid particles were obtained. And some new points were put forward such as the locus of zero vertical velocity (LZVV) of solid particles was not the same as that of liquid, and some particles in inner helical flow could also be separated. The results are of great significance to farther ascertain the separation principle of hydrocyclones and improve the separation efficiency.

Jan 1, 1993

By J Nemcik, E Baafi, I Porter, G Spinks

Spray-on liners used in the mining industry for ground support and stabilisation applications are either cement based (æshotcreteÆ) or polymer based (æthin spray-on linersÆ). Some thin spray-on liners are a blend of both polymer and cement (eg Tekflex). A small number of thin spray-on liners (TSLs) have been trialled in Australia as potential replacements for steel mesh in roadways and other underground mining applications; however, they were found to cure slowly and the cured coatings became brittle after an extended time in place. The University of Wollongong in collaboration with the Australian coal mining industry has shown that a viable polymer-based alternative to steel mesh in underground roadway support applications can be developed to eliminate the use and handling of steel mesh. The work to date has: established the feasibility of developing polymeric alternatives to steel mesh in underground roadway support applications; identified the physical and material constraints to be endured by any new polymeric skin reinforcement system by measuring the mechanical properties of steel mesh; identified materials that can be spray applied; and demonstrated that polymer mechanical properties can be optimised to produce similar mechanical properties (elastic modulus, yield stress, elongation-at-break, etc) to steel mesh. The identified materials will: allow the face support cycle to be fully automated, or at least remotely operated and installed; remove personnel from the immediate face area; and substantially improve underground roadway development rates.

Jan 1, 2008

Due to geographical location, AustraliaÆs economy and trading are closely related to Asia. With ChinaÆs increasing demand on resources and energy and Japan and KoreaÆs steady imports in these fields, AustraliaÆs mining industry is experiencing a so called æboomÆ period. Traditionally, engineers or skilled workers from South Africa, Britian or other parts of Europe moved to Australia for its mining industry. Now, more students from Asia are starting to choose mining engineering (similar choices include mining geology, metallurgy, geotechnical engineering and mining surveying) and expect to work in these fields. How does AustraliaÆs mining industry face such a situation? What kinds of challenges and opportunities do the mining industry and universities face? How do mining companies utilise these human resources? This paper concludes with an analysis of all these questions at an industrial level and some personal deduction as to the preferred course for international students.

Jan 1, 2005

By Radenkovic C, Ivkovic S, Minic I

The model, already tested and applied, enables a highly efficaceous solution of the problem of issuing instructions for interested services on the basis of known contents of in- dividual stages of mine mechanization repair and known time intervals between repairs for specific machines and total mechanization. Application of the model provides work orders for all types of repairs for specific machines or systems, and orders for the commercial department regarding spare parts Supply.

Jan 1, 1977

The general characteristics of bauxite deposits in Temporary Reserves held by Bauxite Exploration Pty. Ltd., Western Australia are briefly reviewed. The deposits (slide) are 'near the eastern limit of the bauxite laterite cap which masks the basement rocks of the Darling Range.

Jan 1, 1964

For various reasons, the maintenance of shaft structures is becoming an increasingly important factor in the operation of underground mines. Deterioration mechanisms related to operation of the shaft are identified as corrosion, mechanical damage, fatigue damage and wear. Deterioration mechanisms related to rock movements are identified as vertical strain, ride vertical closure and squeezing. Analytical procedures for assessing this deterioration are discussed, and it is shown how acceptance criteria are developed and implemented. In order to track the deterioration of shaft structures, shaft inspections are undertaken, but the information is often not well documented. Formalised procedures for capturing and recording information, and then processing the information are presented. Finally, two case studies are briefly described to illustrate how these procedures have been implemented in practice, and what benefit has accrued to the mines concerned.

Jan 1, 2005

International tenders for contract mining opportunities require the Contractor to make an assessment of risk for an operation with a life span of up to twenty-five years usually based on data made available by the Client. This paper seeks to address how the Contractor assesses the data and quantifies the risks associated with the project. The areas of risk are common to most projects, but in the--Lontractor's case, risk assessment is carried out on the Client's data base and within a compressed time frame of usually less than six months. Incorporation of that risk assessment into the contract documentation is also discussed. Practical examples are given in a number of areas.

Jan 1, 1986

By J Rowland

"Ventilation models are invaluable tools for both prediction of routine daily ventilation changesin an operating mine to circuit performance expectations at the mine in 20 yearsÆ time. Arguably ventilation offi cers are becoming increasingly reliant on maintaining an accurate ventilation model with which to do their work. This paper relates to the practical assessment of the accuracy and thus ability of a mine site ventilation model to be reliably utilised on such varied tasks. The author's experience shows that in some cases the incumbent model is found to be in a state of tune that demonstrates a mine wide detailed assessment of branch resistances is simply not required. The money spent on a detailed mine wide ventilation survey that is not required would be far bett er served purchasing much needed monitoring equipment, rather than fixing something that is possibly not even broken. The term ænot rocket scienceÆ has been incorporated into the title of this paper because it appears that many practitioners believe that circuit validation is diffi cult. As long as clear att ention to detail is paid to the actual data collection process then drawing an accuracy comparison between the circuit performance and the model performance at any particular point in time, is really very simple. This paper will show a manner in which a circuit can be analysed to determine its actual state of health by using various diagnostic tools and tips. It will help ensure that subsequent work scopes to address any highlighted model defi ciencies can be more effi ciently scoped and targeted. It will hopefully remind operational people that such self assessments can easily be done æin houseÆ if the appropriate steps are followed."

Jun 1, 2012

By I Lipton

Dilution and ore loss have an important bearing on the success of open pit mining projects. Their impacts on production costs, revenues and production rate require that they are correctly modelled in the long-term mine plan. The estimation of dilution and ore loss is therefore an essential part of any Ore Reserve estimate or mine schedule. Large open pit mines are driven by the economies of scale that are achieved at the cost of less selectivity in the discrimination of ore and waste. Planning for these mines is facilitated by the use of block models for mine design, scheduling and the conversion of Mineral Resources into Ore Reserves. This paper reviews various approaches to the estimation of dilution and ore loss, as implemented in computer block models. In the case of orebodies with well-defined sharp boundaries, rather than irregular stockwork mineralisation, the geological interpretation is a critical factor. Variability in the geometry of orebodies is common within large open pits and must be taken into account when estimating dilution and ore loss. A method of regularisation, controlled by the wireframed geological model, is demonstrated, using examples from large open pit stratiform copper and magnetite deposits. This can be carried out without special computer software modules.

Jan 1, 2007

By K Baker, J Purtill

One of the key challenges for the mining industry globally is the rehabilitation of mine waste, and Queensland is no exception. Out of pit waste structures including waste rock dumps and tailings storage facilities, create novel landforms which require ongoing maintenance and pose risks to the environment and sometimes to communities. Where multiple mines co-exist, such as parts of Queensland’s Bowen Basin, individual mines can often be constrained by adjoining operations. This presents opportunities for broader rehabilitation strategies to be considered, more than the current single mine focus, that may provide better environmental outcomes for a region. Given recent global disasters involving tailings storage facilities, and our team’s endeavours to drive Queensland to achieve leading practice in mined land rehabilitation, we are exploring the potential to maximise in-pit tailings disposal opportunities for coalmines through shared waste management strategies. A shared waste management strategy is where two (or more) mines, owned by different companies and operated under different environmental permits, transport tailings from one mine to the other in close proximity, for disposal in a disused pit. This would reduce the number of waste structures to be built, operated, rehabilitated, and managed in perpetuity. Our objectives are to identify and remove barriers to tailings transfers between sites to:  minimise environmental risk  minimise long-term liability of managing mining waste and associated structures  support improved outcomes for the local community. To determine the scale of coal waste disposal practices in Queensland, internal data and publicly available imagery was analysed by the Department of Environment and Science in 2022. Approximately 6500 ha of land in Queensland is utilised for coalmine tailings storage facilities or codisposal areas, with ≈ 3700 ha of this being out of pit.

Aug 2, 2023

Thrusting is well documented in the Finisterre/Sarawaget moun- tains, the Kainantu-Waf district and in the Highlands between the Kubor Anticline and the Ramu Valley, Papua New Guinea. The thrusts trend NW and involve rocks ranging in age from Permo-Triassic to Plio-Pleistocene. Evidence from the Finisterre/ Sarawaget mountains demonstrates that a major phase of thrust- ing commenced in Pliocene times and continues today. Palaeostress analyses is a sensitive technique for assessing the kinematic history of faulting. The picture gained from the Finisterre/Sarawaget mountains, the Kainantu district and be- tween Kundiawa and Keglsugl is simple, involving a north to northeast ol. Local complexities between the upper Chimbu Valley and Brahmin indicate extension on a NW-N trend. The simplicity of this anlaysis, which accords with seismic and geo- detic strain data, shows that the major faulting in Papuan Orogen is no different from that in the Papuan Fold Belt; that the Papuan Orogen and the Papuan Fold Belt together form a young thrust- fold complex; and that such structures as the Kubor Anticline may be fault-bend folds. Recognition of the obduction of the Finisterre/Sarawaget reef/ volcanic complex over the Australian plate, the gas seeps in the Ramu Valley and foothills of the Finisterre/Sarawaget Mountains, oil seeps in the Goroka and Kundiawa regions, and our interpre- tation of the PNG Orogen as part of the Papuan Fold Belt indi- cates unexpected probability that the PNG Highlands are pro- spective for hydrocarbons.

Jan 1, 1997