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By N J. Betts

This paper aims to build on the strong emphasis that was placed on safety in the Sydney AITES-ITA Congress in March 2002. It will do this by comparing safety records from some major tunnelling projects in Europe and Australia over a period commencing in the second half of the 19th century to the second half of the 20th century and examining reasons for the apparent marked improvement that appeared in the 1980s. Further by looking at the relationship between this improvement and current trends in the australian industry by means of a detailed review of the safety record for the Northside Storage Tunnel project in Sydney which was completed in mid-2000. The paper will conclude by providing a summary of the progressive approach adopted by the minerals industry in australia and summarising the current state of tunnelling and underground construction in australia with respect to recently completed projects and potential major initiatives.

Jan 1, 2003

n One of the most interesting and economically important developments which has .`taken place- in the Kalgoorlie Field over the past twenty .years is the proved penetration of ore into - caicò schist. which:has been established on the North Kalgurli Mine. 'This is quite extensive, both. laterally and ' in -depth, and has occasioned-,'" ccasioned ' " some madification.of geological thought In the search for additional ore sources:. .Ore has been mined in calc schist almost since the' first major: gold::discoveries-were made,. and the principal 'features of the various types of depos:itl are well covered in the literature ' of the field. ' However, occurrences in caic schist have not-been characterised by the same degree of continuity or frequency as the innumerable lode formations in- the more -favourable quartz dolerite, ' and there has been a tendencyAo regard,them as isolated and discontinuous ore bearing structures, occurring only under very special-- conditions. It is not intended-:to describe the whole' range of caic schist ore occurrences in this paper, but only major controlling structures, whose penetration therein has been definitely established, and in which an appreciable .amount.of,_ore.has, been and is still being. found.. . It is considered that -similar stiiictiires: may present a' major objective for future exploratory work in other parts of the field'.

Jan 1, 1964

THE alkaline method for the estimation of zinc cannot, in the writer's opinion, be relied. upon to within very narrow limits between two assayers on unknown quantities of zinc. The end point is not decisive enough, and allows the personal factor toenter largely into the assay. The following investigation was undertaken to see how accurate the acid method is on Broken Hill concentrates and ores, and what should be the limit between the results of two assayers. The method adopted is as follows:Weigh sufficient amount of ore to give titration (between 20 and 50 cc.), place in tall 400 cc. beaker, cover, add 7 cc. nitric acid and heat till brown fumes cease to be evolved. Wash dock glass into assay, add potassium chlorate, evaporate to dryness on a slow fire with the beaker uncovered. When no smell of chlorine or nitric acid is observed, remove and cool. Add 100 cc. boiling water, then 7 grm. ammonium chloride, W cc. ammonia (.880 sp. gr.), boil for five minutes, filter, wash...

Jan 1, 1911

By Hayashida O, Numata Y

Ultraviolet and infrared spectroscopic analyses and the extended lluckel molecular orbital method were applied to determine the electronic and binding states of 2-mercaptobenzothiazole and the adsorption system of 2-mercaptobenzothiazole on pyrite. 2-mercaptobenzothiazole exists rather in thione form than in thiol forru and the two adsorption peaks in solution were assigned to both 7t--?rt* transitions. 2-mercaptobenzothiazole chemically adsorbs on pyrite mainly due to forming the bond between iron (pyrite) and sulphur (2-mercaptobenzothiazole).

Jan 1, 1993

SINCE writing the above-mentioned paper, some further indicator cards have been taken from the No. 1 machine, and the writers believe that a reproduction of these cards will be interesting as illustrating the performance of the machine after fifteen month steady running, night and day, seven days per week and twenty-four hours per day, at the average speed of fifty-seven revolutions per minute (see Fig. 1, page 60). For the past twelve months no adjustment have been made in the valve setting, and the only repairs have been in connection with the springs of the poppet valves, and these but slight, the springs latterly having been removed. The cards illustrated were taken with one indicator, and, therefore, are not simultaneous, andmay show to some extent the yariations of individual strokes, and with that qualification may be taken as typical of the machine's average performance.In connection with some feed-water measurements of the winding engines a rough test was run with the two compressors, the Riedler and the Corliss, coupled to the condenser, and running at fifteen and fifty-seven revolutions per minute respectively, with the result of 15.9 pounds of steam per indicated horse power per hour. This result, though only approximate, seems to indicate that the No. 1 machine is running under the guaranteed consumption, and that it is capable of maintaining this under the severe conditions of everyday practice.

Jan 1, 1909

By Heape JM

Production from the Cattle Grid orebody commenced in August, 1974. This followed a recent discovery arising from an extensive exploration programme involving stratigraphic drilling, geochemistry and geophysics. Located some 4 km west of the original copper occurrences at Pernatty Lagoon the discovery was found to contain 4.6 million tonnes of ore averaging 2.4% copper. The ore is a "sandstone copper" type localised near the disconformity between two Precambrian (Adelaidean) stratigraphic units, the Pandurra Formation and the Whyalla Sandstone. The mineralisation roughly follows the interface between these units and occurs in fractures, vugs and along bedding planes. The mineralogical character of the ore is somewhat complex consisting of chalcocite and bornite, with associated chalcopyrite, sphalerite, pyrite and other less common sulphides. 1. Senior Geologist, Pacminex Pty. Limited, Sydney, N.S.W. 2. Mine Geologist, for Mt. Gunson Mines, Pacminex Pty. Limited, Mt. Gunson, S.A.

Jan 1, 1975

Maximising margins in highly competitive international markets demands superior productivity. A key to superior productivity is using a process approach to enable rapid, ongoing improvement of production, commercial, administrative, marketing

Jan 1, 1998

Sophisticated pit optimisation software has allowed mine planning engineers to generate mining outlines that consider the numerous factors that have a major effect on the success or otherwise of a mine plan. The outlines are generally generated using a range of values for which one can assume a fixed mining cost and a variable revenue. During analysis, the expected costs and revenues are used to investigate the cashflow and sensitivities. Ultimately, the final pit and incremental outlines, or shells, are selected for a given expected price. This paper proposes an alternative method for incremental pit shell selection that considers the risk the mine be prepared to accept. The life of mine is divided into a number of Business Risk Periods (BRPs). The BRP represents the period of time over which the owner is prepared to invest capital. During each BRP, the mine will then operate at a selected investment cost which is generally equal to or greater than the minimum required to meet production targets. In this way, a robust mine plan can be produced which allows the mine to react to change without having to alter the incremental shell limits while maintaining a strategic risk profile. This paper will summarise factors to be considered in selection of the BRP and the incremental pit shells within the BRP.

Jan 1, 1998

By Chavant G, Begis D, Gunther J

To study the ventilation of a mine (improve on the existing situation, examine extension projects) the calculation program used must take into account all the resistance values in the branches of the network. These resistance values are generally determined by measurements, which are accurate to a greater or lesser extent. In order to arrive by calculation at the flowrates measured :n the mine at a given moment, the resistance values have tto be adjusted experimentally. This manual operation is lengthy and delicate.

Jan 1, 1988

Batterham and Algie began their paper on: `The role of technology in the minerals industry' (1995) by noting that while: it is often stated that innovation is central to the economic survival of mining and minerals processing in the face of global competition, .. . technology is often far from a core strategy in our industry. This point is correct. Throughout the world, as a broad generalisation, mining companies do not value technology development as a principal means of gaining competitive advantage. It is important to understand why this is the case. Batterham and Algie address this question by making distinctions between innovation, technology and research. They note that while: all successful (mining) companies are good at innovation . . . that innovation can proceed without any research and development and that it is innovation that generates the competitive advantage, not research and development per se. In this paper we accept these arguments. However, our focus is somewhat different. Whereas Batterham and Algie took a mining company's perspective on the technologies of mining and processing, we take a broader view of the opportunities for technology development for company Australia but, in order to focus the argument, we restrict our discussion to the area of mining (rather than processing); we focus particularly on mining systems and mining equipment. We begin by looking at the motivation of companies operating in any industrial sector to invest in research and development. Figure 1 recognises four levels of industrial maturity. For companies in the embryonic and growth stages R&D often is essential to initiating and developing the business. Mining, on the other hand, is a mature industry. In mature industries the conventional roles for R&D are to reduce costs, to extend product differentiation, or to develop new technology with the aim of rejuvenating the business. Next we ask whether these general-industry arguments apply to the mining industry. If they do then the mining industry should value R&D more highly; after all cost reductions and business rejuvenation are goals that are worth achieving. On the other hand if, for whatever reason, these general arguments do not apply to mining then this may lead the mining industry to invest only modestly, or not at all, in R&D. In this event, while this may be a rational decision for the mining industry, it may not be in the best interest of a nation like Australia where revenues from the sale of mineral products represent an important part of the country's economy.

Jan 1, 1997

Although the 'exi'stence of bauxite in Australia has been known for many years it is only recently that exploitation has commenced.. of the two most' important` deposits, strangely at almost diagonally opposite tips of the continent. Recognition of the importance. of the bauxite in the South/West corner came about initially through the efforts of a well-known Australian mining company which,` with some outside financial help, tackled the early exploration with commendable foresight and courage.

Jan 1, 1964

The reliable estimation of ore reserves in mineral sand deposits depends on drilling methods and assay techniques that have been specially developed within the industry. Improvement of these techniques is a continuing process, as variations within and between deposits are highlighted during the actual mining operation. Constant monitoring of metallurgical losses along with mineral production allows comparison of mineral tonnages accounted for by mining, with original calculated reserves. A review of ore reserves in the Jerusalem Creek field from scout drilling in the sixties, through mining in the seventies, shows the progression from understatement prior to mining, to the present when more than two thirds of the reserves have been depleted.

Jan 1, 1979

By Zhang P, Wang T, Duan X, Sheng T, Kong L, Wang Y

This paper puts forward an artificial neural network (ANN) for the forecast of deformation of the surrounding rock deformation. On the basis of this, this paper gives some examples of its application. The results show that the ANN model has a high forecast accuracy.

Jan 1, 1995

By J K. de Wet, G Balassone, J D. Singleton, V Arseneau

The Accha-Yanque zinc belt in southernPeru is a major zinc-lead rich metallogenic province. In the belt are comprised several non-sulfide-type occurrences, extending on the periphery of the Yauri-Apurfmac batholith (Oligocene-Miocene). Zinc mineralisation at Accha (almost fully oxidised) occurs in breccias of sedimentary and tectonic origin in the limestone of the Ferrobamba Fm (Middle to Upper Cretaceous). Non-sulfide association consists mainly of smithsonite and hemimorphite replacing both primary ore minerals and carbonate host rocks. Mn(hydr)oxides and Zn-clays (sauconite), can be locally very abundant. Differences in mineralogy of the ore and gangue minerals, as well as the composition of the host rock can have a profound impact on zinc recovery and reagent consumption, and therefore on the economic value of the deposit. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By G Ferguson a, P Carrasco, P P. A Dowd

International codes of practice offer broad definitions with respect to the classification of resources in terms of risk. Specific guidelines and protocols, to analyse sample data, carry out geostatistical appraisals, develop geological models and finally estimate and classify resources, are not addressed. Neither are detailed requirements for engineering mineable reserves from estimated resources. In addition, international codes of practice fail to distinguish between types of deposit, other than in broad terms, as for example, The AusIMM JORC Code (JORC, 1999) which makes reference to diamond and coal deposits. The objective of this paper is therefore to set in motion the process of specifying detailed protocols, acceptable to the international community, for the assessment, reduction and management of risk associated with the development and extraction of mineral deposits. Ordinarily, the main risks and issues encountered during the process of estimating resources and subsequent conversion to reserves, encompass:failure to understand relevant geological controls of mineralisation; validation of grade interpolation; optimism in geotechnical appraisals of dilution and stability and the consequent selection of inappropriate mining methods; metallurgical modelling of minerals and contaminants reporting to concentrates; appraising the hydraulics of heap leaching and the numerous factors that can affect recovery; difficulty of managing metal price cycles and changes in regulations within the constraints of long-term mining plans; and development of better evaluation techniques for mining ventures. Uncertainty is inherent in estimation and engineering work, and its identification, reduction and management should be a fundamental goal of all involved in the mining industry (Figure 1). Variability may be reduced by:following internationally accepted practices for the collection, manipulation and analysis of geoscientific data; and verifying that the procedures actually performed meet the associated standards. Increasing amounts of data will also reduce uncertainty, but only if the procedures used to collect and appraise such data follow the relevant procedures. It is thus the aim of a series of papers in preparation, Beniscelli et al (in prep), to put forward detailed guidelines, for:project sponsors û to provide a global view of the work and documentation needed to support requests for funding various phases of project development and budget approvals; geologists û to indicate a checklist of the requirements and standards for the exploration and estimation of resources; and engineers and economic analysists û the protocols for characterising, modelling, engineering and evaluating the extraction of reserves. It is therefore hoped to encourage the development of consistent standards for declaring reserves within the mining industry. Data from projects and operations will be utilised to illustrate the benefits of adopting a rigorous approach to estimating resources and engineering reserves, Beniscelli et al (in prep).

Jan 1, 2000

By Jiricek F

Legislative change has reformed the licensing process in Victoria. The Mineral Resources Development Act 1990 and the two stage system of licensing with the authority to commence work is discussed. A key part is the requirements of planning consent, being either an Environmental Effects Statement or the issue of a Planning Permit prior to the issue of an authority to commence work for mineral extraction. Examples of recent experience is discussed.

Jan 1, 1997

The P49 Shaft, Hilton Mine, was sunk and equipped for Mount Ise Mines Limited by con- tractors Cementation - Thiess Joint Venture. The leached siltstones to a depth of 150m were known to contain large volumes of water. These siltstones were cored and tested in the laboratory. Field results confirmed that cement grouting was relatively ineffective but that chemical grouting was effective. The Sm diameter shaft was sunk to a depth of 1040m. Weak strata to the full depth re- quired continuous temporary support by rock bolts and mesh before the concrete lining was poured, and made sinking conditions difficult. After completion of the shaft sinking the headframe was redesigned and modified to allow shaft equipping as a combined service and hoisting shaft with seven compartments. The shaft steelwork was designed and fab- ricated for service with high speed conveyances operating under corrosive conditions. The steelwork, weighing approximately 1500 tonnes, was installed to a high degree of accuracy which required guides not to depart from true verticality by more than 2mm over any 5m, or 15mm over the full shaft depth.

Jan 1, 1976

By Carlie JC

Many low sulphidation epizonal gold and zinc-lead vein deposits within magmatic arcs are situated on basement highs, and post-date both the main volcanic episode and porphyry copper (gold) mineralization. These features are best explained by emplacement of a flat batholith a few kilometres beneath each mineral district, as recently demonstrated by geophysical data in the Baia Mare district of Romania. The batholith provides heat for the hydrothermal system, and results in extensional faulting both through up-doming of the overlying rocks, and in some arcs through incipient collapse of the thermally weakened crust under regional extensional stress. More water-rich magmas emplaced at greater depths could explain some deep epizonal and mesothermal gold deposits situated outside magmatic arcs.

Jan 1, 1995

By K Lee, K Fernando, S Rayner

Copper-gold ores have been technically difficult and uneconomical to process due to high consumptions of cyanide. Many copper oxide and sulphide minerals react with cyanide to form copper cyanide complexes, partly contributing to the high level of weak-acid dissociable cyanide in the tailings which is normally experienced during the processing of copper-gold ores. The cost for detoxification, if required for treating these tailings, would further inhibit the development of these copper-gold resources unless the cyanide used for leaching was recovered. Several technologies have been proposed to process copper-gold ores, aiming to recover copper as a co-product and cyanide for recycling in conjunction with the leaching process. A critical review of these processes reveals that a pre-concentration stage (solvent extraction or resin ion exchange) is required. Cyanide is recovered by the conventional Acidification-Volatilisation-Regeneration technique in most cases. A critical evaluation is also provided on technical aspects related to the use of Vitrokele Technology and a newly developed Elutech process in processing copper-gold ores, in particular with its application at May Day Mine.

Jan 1, 2000

By A von Johannides, G J. van Hout, L F

In the past various systems have been used to plan the extraction of ore from block cave operations. These systems have varied from rather sophisticated models with empirical ægravity flowÆ rules applied to the very rudimentary models where only the recorded mined tonnageÆs have been accounted for against the available resource. The normal requirement of these models has been to only plan the movement of ground through the drawpoints. Little cognisance has been taken of the other parameters that affect the total mining operations. The intended purpose of the linear program planning system is to not only include the management, resource availability and geotechnical constraints, but to also include the mining rules. The paper will discuss the various constraints that have been considered, and attempt to illustrate where the system better serves the production system than previous ones. A brief technical discussion on the linear programming system is included.

Jan 1, 2000