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By Witkowski A

I have the pleasure to present 6 excellent papers in this section all of major relevance to the mining environment of today where competing social, legal and monetary interests and their often complex interaction require serious consideration. This is particularly true today where huge fluctuations in commodity prices makes mining a perilous undertaking while the world increasingly are becoming aware of the serious threat that mans activities has on his environment. The 6 papers deal with such complex issues as safety in an underground environment; How to protect sensitive wetlands well into the next century; The enormeous waterproblems in China and conflicting dewatering/water supply needs; Disposal of contaminated water in sensitive areas and the dynamic interaction between mining companies and legislation.

Jan 1, 1988

By J A. Braithwaite

Social licence to operate is not a new concept for the mining industry, referring to stakeholder approval or acceptance for the activities and impacts of a project, company or industry. It is intangible, dynamic and non-permanent, hence it needs to be earned and then maintained (Thomson and Boutilier, 2014). It has also been argued that social licence extends beyond building approval or acceptance, into engagement for long-term development (Owen and Kemp, 2012).There are many examples where stakeholder opposition – or withdrawal of social licence – have increased capital and operating costs, extended schedules and impacted reputation. At its extreme, the withdrawal of social licence to operate can also contribute to or be the catalyst for mine closure.The key benefit of obtaining a social licence is a reduction of risk. Stakeholder support and advocacy, as well as the implementation of social performance programs that contribute to social licence, can be beneficial in terms of schedule, costs and other benefits.While decisions to close a mine are generally driven by resource availability or economic conditions, the social, economic and environmental legacy remaining post-closure is of importance to many stakeholders. With a number of significant mines now approaching closure within Australia, we are seeing heightened community concern about the economic and social impact of mine closure and the success of land rehabilitation. So how does the concept of social licence to operate extend into the closure phase of the mining life cycle?CITATION:Braithwaite, J A, 2016. Social licence to close?, in Proceedings Life-of-Mine 2016 Conference, pp 176–179 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

The constructionhunnelling industry in Hong Kong has taken an upturn during the last few years due to the commencement of works to relocate the International Airport to Chek Lap Kok Island. The Airport Core Program consists of ten individual projects including roads, landfill, bridges and tunnels to build the airport and link it to the mainland of Hong Kong. Part of one of these projects is Cheung Ching Tunnel located on Tsing Yi Island. The proposed tunnel consists of a 1.6 km twin tube road tunnel through the island's central ridge, taking three lanes of traffic each way. Each tunnel is 16 m wide - (the widest road tunnel in Hong Kong) and are 10 m high. ICI Explosives (China) saw an opportunity to supply bulk explosives to the Cheung Ching tunnel and contacted ICI Australia to determine availability of a bulk system for tunnel blasting, and assist in its introduction. This paper discusses the methodology behind developing that bulk system to suit a large tunnel drill and blast operation. It also looks at the problems encountered along the way, from the development of the product to the application of the system in the tunnel and the eventual success of introducing a bulk system into a large tunnelling project.

Jan 1, 1994

The control objectives and constraints for grinding circuits are ana- lysed, taking a single-stage ballmill-cyclone circuit as an example. The design of a hierarchical modular control system is described, for implemen- tation on modern microprocessor-based control systems. Product sizing measurement is identified as a problem area, and a new approach to product sizing inference, from on-line cyclone feed and overflow measure- ments, is presented. The procedure over-comes several practical difficulties of a previously proposed inferential method and is therefore expected to find application in more advanced grinding circuit control systems.

Jan 1, 1988

By P Trotta

The majority of water to the Olympic Dam mine and the nearby townships of Roxby Downs and Andamooka is supplied from the Great Artesian Basin (GAB). There are no permanent local water sources available to Olympic Dam. The use of water from the Great Artesian Basin by Olympic Dam receives considerable attention by BHP Billiton and is extensively regulated by the Government of South Australia. Olympic Dam has robust business management systems in place to ensure the sustainable use of water from the GAB including ISO9001 and ISO14001 systems to deliver the targeted outcomes and obligations of the Olympic Dam Environmental Management and Monitoring Program. The management systems ensure that Olympic Dam retains accountability for its water demand from the GAB over the life of the mine. This accountability has delivered continuous improvement in water use efficiency driven by operating discipline, implementation of water saving projects, using water on a fit for purpose basis including substitution from non-GAB sources, and risk management to prevent and mitigate water supply disruptions to Olympic Dam and Roxby Downs. Since the establishment of Olympic Dam, BHP Billiton has funded a reduction in GAB water flow from bores, previously going to waste, that is greater than the annual average flow used by Olympic Dam.

Jan 1, 2009

By Shiels O. J

The major Permian coal deposits of N.S.W. are in the Sydney-Bowen Basin and associated small deposits occur in structurally isolated areas; a further deposit is present in the Oaklands Basin. - The Sydney-Bowen Basin in New South Wales comprises the sub basins, the Sydney Basin and the Gunnedah Basin. Coal measures in these basins are near the top of the Permian succession and within and below an underlying marine sequence. The coal deposits can be conveniently described in units in which the coal geology is homogeneous. The Clyde Coal Measures and Yarrunga Coal Measures contain no seams of economic significance and occur beneath the marine beds in the south of the Sydney Basin. The Greta Coal Measures are economically significant and represent a brief interlude in the marine sequence in the north of the Sydney Basin and equivalents are present in the east of the Gunnedah Basin. The Tomago Coal Measures crop out above the marine sequence east from the Lochinvar Anticline and dip southeast to uneconomic depths. The Newcastle Coal Measures are historically and economically very important and overlie the Tomago Coal Measures and these measures will continue to be important although future mining will be faced with greater depths. To the west of the Lochinvar Anticline the Singleton Coal Measures, equivalent to the Tomago and Newcastle Coal Measures, crop out. This unit represents the thickest development of coal measures in the State and has a very large potential for both open cut and underground mining. Equivalents of the Singleton Coal Measures, the Black Jack Coal Measures and the Booroomin Group crop out on the east side of the Gunnedah Basin and probably are widespread across the Basin. They have less economic potential than the Singleton Coal Measures. In the southwest of the Gunnedah Basin, Illawarra/Singleton Coal Measures crop out over extensive areas and possibly have a large potential for underground mining under low cover. The Illawarra Coal Measures are exposed along the western margin of the Sydney Basin and thicken as they dip into the Basin across a shelf. The outcrop area is currently mined and the shelf has considerable potential for future mining. The highest rank coals in the State are in the Illawarra Coal Measures in the south of the Sydney Basin. The deepest coal mining is in this area and its continuing success is of great importance to the future exploitation of the resources of the Basin. The Tomago, Newcastle, Singleton and Illawarra Coal Measures extend into and meet in the central area of the Sydney Basin but they are under thick cover and are not considered to be economic at present. Permian coal measures occur in isolated areas in the New England Fold Belt and have limited economic potential. The Oaklands Basin in the south of the State contains a large reserve of low rank coal.

Jan 1, 1975

Recovery of tin and copper from concen trates containing cassiterite, stannite and chalcopyrite was studied in laboratory-scale tests designed to simulate continuous operation of the matte fuming process in which tin is recovered as SnS fume while copper accumulates in the matte. Charges made up of 300g of mixtures of the concentrate and siliceous flux were added at a uniform rate in pelletized form to crucibles containing 300g of matte and 50g of slag (both of which were recovered from previous tests), while blowing through the matte with air or oxygen-nitrogen mixtures at a rate of 3 to 5 1/min. Accurate material balances enabled the effects of process operating conditions on tin recovery and sulfur utilization to be deter- mined. When operated correctly, the matte fuming process gave tin recoveries exceeding 90 percent in spite of wide variations in the copper content of the matte and in the operat- ing conditions. Deterioration of tin recovery was associated with undersaturation of the slag with respect to silica, and with high partial pressure of sulfur dioxide (greater than approx- imately 0.2) brought about by oxygen enrichment of the blowing air. The utilization of sulfur varied widely in low grade mattes. Copper in excess of approx- imately 10% promoted formation of SO2 by the commonly accepted reaction: FeS + 1-120 2= FeO + S02 while in copper-free and lower grade mattes a substantial fraction of the oxygen was consumed in the alternative reaction FeS + i 02 = FeO + z S2.

Jan 1, 1980

By Osborn G

The bulk flotation behaviour of an industrial rougher bank has been determined with a view to characterising the size iepend ent behaviour of the identifiable nineral groups present. A relatively simple flotation model, based on first order kinetics and the assumption of perfect mixers in series ias been used to provide a fit to the operation of the cells. The adequacy of the model is discussed in relation to the characteristics of the ore and the size iependancy of the parameters. It is shown that improved fits are possible if the model accounts explicitly for this size dependancy and demonstrated how the model may be of use in prediction of the grade recovery relationships for different operating conditions as an aid to plant optimisation.

Jan 1, 1986

A nine-month investigation was conducted into the effect on coke quality and blast furnace operation of the addition of bentonite and southern coal to the northern coal fed to the coke ovens at the Newcastle steelworks.Additions of 0·3 per cent bentonite or 25 per cent southern coal to the northern coal increased the coke strength from 15-20 A.S.T.M. stability to 25-30 A.S.T.M. stability. It is likely that improved mixing and blending facilities would, in both cases, give a coke of over 30 A.S.T.M. stability.For the same coke strength, the use of 0 3 per cent imported Wyoming bentonite was considerably cheaper than the use of 25 per cent southern coal, but the use of Australian bentonite promises the same coke strength for still lower costs. Other additives such as coke breeze, charcoal, iron ore fines, and certain other finely divided materials, gave relatively minor improvements in coke quality.There appeared to be sufficient improvement in blast furnace operation and production to justify full scale addition of bentonite to improve coke quality, although other variables, particularly iron ore physical quality, overshadowed on many occasions the effect of coke quality. Further coke trials with southern or bentonite will be carried out when ore quality has been improved by the introduction of ore sintering at Newcastle.INTRODUCTIONDuring the period of operation of the Newcastle coke ovens and blast furnaces from April 1960 (when No. 3 blast furnace was blown in after rebuilding) to December 1960, a bentonite coke trial was carried out based on earlier research findings (Gregory, 1959a, 1959b; Felton and Gregory, 1960; Gregory, 1960) that as little as 0 3 per cent to 05 per cent bentonite clay added to northern N.S.W. high volatile coking coals gave a significant increase in coke strength. The bentonite coke trial was followed by trials...

Jan 1, 1962

Zinc alloy castings continue to account for a very large, world-wide end-use market for zinc. However, an ever expanding multitude of other materials and processes are increasingly providing viable, cost-effective alternatives to designers, many of whom have no particular allegiance to any one industry. In order to meet this challenge, innovation of and for the zinc hot chamber pressure die casting process, in concert with sustained and inventive market development, is clearly required. While 'Quality' is now the watchword, and the goal of zero defects is being rigorously pursued, other important goals which must be addressed include net shape casting, enhanced productivity and increased energy efficiency. The paper gives an overview of several practical, process-orientated, projects designed to help achieve these goals. For example, a project designed to understand and precisely measure dimensional changes of castings with time has provided some of the critical information needed for net shape casting. A second study is looking anew at surface quality in relation to process conditions as an important step toward the goals of zero scrap rate and increased productivity. Developing the correct die casting machine parameters for achieving optimal quality and properties of zinc (ZA) die castings is a further example of research designed to benefit both the die caster and his customer, chiefly the original equipment manufacturer (OEM). A project on die soldering or galvanising in response to varying process parameters is similarly being considered in order to foster increased understanding and avoidance of problems, with a special interest in the use of special coatings. The maintenance or expansion of the future market for zinc die casting alloys also depends on design for functional applications, as an adjunct to their traditional decorative use. The role that alloys with enhanced properties can play, such as ZATEC, a new high creep resistant alloy developed specifically for elevated stress/elevated temperature applications, will be briefly discussed.

Jan 1, 1993

There is a difference in design aspects between steel linings and rubber linings for grinding mills. The basic design rules for rub- ber are described as well as the liner designs for different applications.

Jan 1, 1978

By S S. Kanchibotla, D La Rosa, R W. Pesch

The Porgera Joint Venture and Dyno Nobel have commissioned a joint project to optimise the drill and blast operations to increase the overall profitability of the mine. One of the aims of this project is to increase the throughput of semi autogenous (SAG) mills by optimising the blast fragmentation. A number of test blasts were conducted during the period May 2000 to January 2002 and the ore from these blasts was campaigned through the mill. The data from these trials suggested up to 15 per cent increase in the SAG mill throughput with high energy blast designs. However, changes in ore geology (shape, structure and hardness) and potential ore dilution/loss and wall damage have raised concerns about the economic benefits of these designs over the entire orebody. The lack of a system to track the economic benefits of these modified designs has also compounded these concerns. PJV and DynoConsult, the consulting arm of Dyno Nobel have initiated steps to minimise the potential for ore dilution and wall damage resulting from these modified designs. DynoConsult worked with Julius Kruttschnitt Mineral Research Centre (JKMRC) to develop and implement a blast management system to track the quality of blast implementation and down stream process benefits. This paper discusses the implementation of the system and the results achieved to date.

Jan 1, 2003

By Webster SS

This paper uses computer modelling tech- niques to compare and contrast anomaly patterns obtained with fluxgate (vertical field) and proton precession (total field) magnetometers at typical latitudes in northern and southern Australia. The use of these modelling tech- niques is suggested as an aid to magnetic interpretation and field examples are included from Tasmania and the Northern Territory.

Jan 1, 1975

The Rock Mass Rating (RMR) and Rock Mass Strength (RMS) classification systems for jointed rock masses are briefly reviewed, with particular reference to their use in slope stability studies. A correlation is provided between the results obtained from the two classifications and an equation is presented tentatively defining the RMR value for long-term stable slope angles. The validity of the equation is discussed in general terms in the context of slope stability problems commonly encountered in Western Australian open pit gold mines.

Jan 1, 1992

By Fiedler VA, Threadingham GM, Leckenby DF, Clarkson CJ

The Utah Development Company Research and Development Laboratory has embarked upon a programme of optimisation of the company's coal preparation plants. This goal is being accomplished in a three-fold manner - use of pilot plant equipment for optimisation and modelling of the various unit operations, evaluation or development of on-stream ash analysis for process control, and evaluation or development of alternative processes. In each of these areas, digital data acquisition- and at a later stage, process control feedback, is being extensively utilised, based largely upon the use of the HP85 and HP9915 desktop computers. A variety of input/output configurations such as HPIB, BCD, GPIO are used, and at times supplemented by microprocessors such as the Intel 80/05 to assist in data transfer. This paper will discuss a number of specific projects, especially in relation to the manner in which the variables are monitored, and the data later retrieved and analysed.

Jan 1, 1983

By Jones KW, McClelland RA, Denholm WT, Taylor RN, OÆShea J

Associated Tin Smelters, Sydney, are developing tin smelting operations in a prototype commercial SIROSMELT plant comprising two furnaces of 5 to 8 tonnes capacity. Features of the plant and its operation are discussed and results of its application to tin slag reduction and high-grade tin concentrate smelting are presented. Development work is still in progress but experience indicates that the technology has potential for lowering the costs of tin smelting and relieving constraints on grade and iron content of concentrate imposed by conventional technology.

Jan 1, 1984

By Johns A. L

The concept of the Melbourne Underground Rail Loop and the organ- isation to achieve its construction are covered in the companion papers (Reference 1, 2) and will not be repeated here. The Victorian Railways, as well as being the eventual operator of the Loop when it is completed by MURLA, have also been responsible as "Contractors" to MURLA for the construction of the "cut and cover" or "box" tunnels and related approach works located on existing Railway property. These tunnel connections link the existing suburban system to the new underground works. The following tabulation indicates the significant work volume involved in this cut and cover tunnelling exercise and which is covered in some detail by this paper.

Jan 1, 1981

Controlled Source Audio Magnetotelluric (CSAMT) surveys were carried out by Glass Earth (New Zealand) Limited (Glass Earth) in 2006 - 2007 to investigate epithermal gold targets in the central North Island of New Zealand. The surveys were conducted using a Zonge GDP 32 8-channels receiver and a Zonge XMT 32 transmitter powered by a 16 KW generator. The electric field dipole was maintained at 20 m length (five dipoles per 100 m spread) and the frequency ranged from 4 KHz to 4 Hz. Only scalar (TM mode) signals were recorded, using one magnetic coil per spread. The transmitter bipoles were 1 - 4 km in length and located about 5 to 10 km from each survey area.   Sixteen individual target areas were surveyed by June 2007. The CSAMT survey lines (100 - 400 m spacing) were determined mainly on results from previous ultra-detailed airborne magnetic and gravity surveys conducted by Glass Earth in 2005. The data from each CSAMT line was carefully examined to remove any spurious signals and processed using Zonge SCS2D software, which can produce smooth 2D resistivity inversions of the field data. The results were presented as resistivity sections and maps to help the identification of exploratory drilling targets, mainly from the existence of subsurface high resistivity zones (resistors) that can be interpreted as caused by silicification associated with epithermal mineralization.   An example of processing and interpretation of the CSAMT data is presented in this paper on results from Glass EarthÆs Tahunaatara target, where CSAMT surveys have identified zones of epithermal mineralization confirmed by exploratory drilling.

Jan 1, 2007

The introduction of large diameter holes to underground mining has provided the first opportunity to apply near spherical charges in production scale blasts instead of the convent- ional long cylindrical charges generally used in stope and pillar mining. A modified version of the cratering prin- ciple was applied in the blast design in extrac- ting ore across a horizontal area of a stope or pillar. The new rock breaking technique has developed into the Vertical Crater Retreat (VCR) mining system and eliminated raise boring, slot cutting and dilution of the ore by back- fill material. Furthermore it has reduced labour and time requirements thus becoming not only a low cost method of mining but the safest method of underground mining known today. Exceptionally fine muck is provided with a minimum of damage by blasts to walls and re- treating backs of the stope or pillar. The VCR method can also be used for drop- raising, and for the excavation of underground cavities for almost any purpose . The proper explanation of the breakage mechanism of the near spherical charges opposite to the cylindrical charges yet to be found. The mining industry has quickly recognis- ed the value of the VCR mining method which is being adopted by an increasing number of mines

Jan 1, 1978

By Cheung L. C C, Maconochie A. P

SIROFRAG is a computer-based imaging system that quantifies the post-blast rock fragment size distribution in a muckpile in a mine environment. Improvements in blast performance and blast modelling are being hampered by a lack of a quick and objective method to evaluate the major result of the blast: the fragment size distribution. This is usually done by hand digitising muckpile photographs: a labour intensive and tedious process. SIROFRAG is being developed to quickly, cheaply and objectively provide this information. SIROFRAG is based on active stereo image analysis. It uses a light stripe to illuminate a muckpile and a pair of video cameras to determine the 3D nature of the scanned objects. The imaging system is based on a novel prototype scanning projector that allows images to he captured in full daylight. The Microsoft Windows based software controls the projector and interprets the captured images to provide a size distribution of exposed rock fragments.

Jan 1, 1995