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In December 1997, a series of new environmental legislation was enacted including:ò Environmental Planning andAssessmentAmendmentAct 1997; ò Contaminated Land ManagementAct 1997;ò Protection of the Environment (Operations) Act 1997; ò Native Vegetation Conservation Act 1997; andò Pollution Control (Load Based Licensing) Act 1997.These new Acts will have varying degrees of impact on the coal mining industry in New South Wales when they commence later this year.

Jan 1, 1998

The future of the Tasmanian mineral industry can only be estimated from a knowledge of the past, and armed with this knowledge an orderly plan for the future can be developed. Brief mention is made of the major historical developments through to the present day, with past and future development areas clearly mapped. Areas of importance which have been discussed are divided into the mining of metals, fossil fuels and non-metals; and the process- ing and extractive industries. Discussion then follows on the current general non-insular pressures on the mining industry, the energy crisis, scrap, world shortages, new techniques, inflation, and the effects of exploration on the environment. This is then followed by a discussion of the advantages of Tasmania as a mining state and a cataloguing of the present exploration and some possible areas of future development. From this a suggested plan emerges for the future development of the Tasmanian mineral industry, to incorporate the latest technological advances and by planning to meet the challenge of survival and growth in a turbulent environment.

Jan 1, 1977

By Hungerford F

Long-hole drilling technology has rapidly advanced this decade beginning with rotary drilling/pump down camera surveying and culminating in down-hole motor drilling with cableless electronic surveying over the past two years. With the latter system, a high level of directional control is achievable in boreholes up to 1000m long. Past long-hole drilling across the industry has seen a mixture of success and failure. With these experiences, new and improved techniques and equipment have evolved. A number of long-hole drilling options are available as variations on the basic rotary and down-hole motor methods. They involve different levels of cost and equipment and vary in their suitability in different geological environments and definition of targets. Long-hole drilling is mainly target applied, either in defining geological structures in greater detail, or proving important mining areas such as longwall blocks, to be free of structures. Successful drilling hinges on a combination of drilling expertise, quality and appropriateness of equipment, understanding of geological conditions and good colliery support. Drilling expertise forms part of sound interpretation through keeping relevant records, understanding the reasons for changes in drilling conditions and implementing specific tests such as coring. The final interpretation builds upon all other available geological information. There is still scope for research into improved techniques and equipment. The use of long boreholes for geophysical surveys has high potential.

Jan 1, 1988

By Hayes P. C

In commercial mineral processing operations it has been found that the conditions in the drier have a considerable effect on the subsequent electrostatic separation of nttile and zircon. Laboratory scale studies simulating these heat treatment processes have shown that the electrical conductivity of nitile varies markedly with treatment temperature, time and gas composition. The zircon on the other hand is unaffected. By increasing the electrical conductivity of the rutile, significant increases in separation efficiency can be achieved. Electron microscope investigations have shown the increase in electrical conductivity to be associated with the production of planar defects in the crystal lattice.

Jan 1, 1991

By Orrock G, McKee DJ

Mathematical models of autogenous and semi-autogenous grinding mills have now reached a stage of development where they can be usefully applied to practical problems. In particular, the models are suitable for inclusion in simulations of grinding circuits to study the effects of cir- cuit changes, variations in ore type and changes in throughput. The paper describes a simulation study of the Elura grinding circuit where the empha- sis was on investigating methods of reducing product size from an autogenous mill-ball mill grinding circuit.

Jan 1, 1988

By Thompson J

A programme of testing and evaluation has been in progress at Isa Mine for the last four years with the objectives of rationalising ground support practices, improving installation quality and increasing productivity of ground support functions.Numerous innovations have been successfully implemented. These include the introduction of swellex rockbolts as the major form of temporary support, the use of splitset rockbolts as the primary means of support for the hangingwalls of cut and fill stopes and the introduction of dowels with pumped cement for general long term support.The installation of swellex bolts has been successfully mechanised throughout the mine using Tamrock automatic rockbolters and Atlas Copco BUK 11R drilling rigs modified for this purpose.

Jan 1, 1985

By Kidman B. E

The Fitzpatrick area is the deepest section of the North Mine, with the orebody located between 1450 and 1800 m below the surface and some 600 m NE of the main No. 3 Shaft orebody and separated from it by the intensely sheared Globe Vauxhall Shear Zone. Development towards the Fitzpatrick area commenced in 1977 after earlier initial exploration drive development. However, it was not until 1982 that mining in the Fitzpatrick area actually began with the silling out of No. 36 level at a depth of some 1600 in. Since that time mechanised cut and fill mining from an incline ramp system with connecting stope accesses has progressed some 25 m above No. 36 level. Initial sill development on No. 37 level at 1660 m depth also commenced in July 1987 to further develop the Fitzpatrick area.

Jan 1, 1988

The known coal resources of South Australia are either of poor quality, or expensive to extract, or both. Export quality coal occurs only at great depth in the remote north of the State; the balance of the State's coal resources are suitable only for local electricity generation. Currently there is only one coal mine in the State, at Leigh Creek. This provides fuel for approximately 34% of the State's electricity generation, the balance being fuelled by natural gas. In the near future, new fuel sources must be developed to augment diminishing supplies of natural gas, and to cater for increasing demands for electricity. The South Australian Government has determined that future electricity generation will be based on the combustion of local coals. The geological and geographical environment of the known coal deposits and the quality of these coals are such that the most up to date and innovative technology must be applied to both extraction and combustion processes. The Government, the Electricity Trust of South Australia, and several Australian and overseas companies have embarked on an extensive research and development programme to ensure that these otherwise useless resources can be developed to the benefit of the State.

Jan 1, 1987

By Waters JC

Pseudoclastic hydrothermal alteration textures occur within quenched coherent dykes forming part of a subaqueous dome complex (-4 Ma) on Ponza Island, Italy. These textures are similar to those observed in considerably older (-500 Ma) subaqueous volcanic rocks at a number of localities throughout the Mount Read Volcanics in Tasmania and elsewhere in ancient volcanic sequences of this type in Australia. This is significant because the processes of formation, hydrothermal alteration and secondary mineralisation of ancient volcanic sequences may be better understood if we can make comparisons with modern analogues. Observations at Ponza imply that these pseudoclastic alteration features form synvolcanically or immediately after dyke emplacement and lava extrusion. This is compatible with scenarios presented for their formation in ancient sequences in the Mount Read Volcanics, Tasmania.

Jan 1, 1995

To counter depressed world nickel prices, a continuing effort is being made at Kalgoorlie Nickel Smelter to reduce unit production costs. One major area in which production costs can be reduced is the substitution of coal for fuel oil. Two areas where this has been achieved to bring about a saving are, the addition of coal to flash furnace flux to reduce supplementary fuel oil requirements in flash smelting and the replacement of two oil-fired air preheaters with a coal-fired unit. These actions have resulted in coal replacing 67% of the current fuel oil requirement in flash smelting at the Kalgoorlie .Lckel Smelter.

Jan 1, 1987

Australian continental crust has accreted and consolidated by thirds: 1/3 during Archean time, 1/3 during Early to mid-Proterozoic time, and 1/3 during latest Precambrian to mostly Paleozoic time. The progression of orogenic systems and the crustal consolidations they represent seem not fundamentally different in basic orogenic processes from better known Mesozoic-Cenozoic examples in that accretionary, continental margin, collisional, and intraplate intracratonic inverted and/or reactivated systems are all recognizable in the tectonic evolution ofAustralia.

Jan 1, 1995

Krupp Polysius AG, FRG, in close cooperation with Prof. Dr. K. Schoenert, FRG have developed the principle of the high pressure grind- ing roll POLYCOM. The POLYCOM mill basically consists of two counter-rotating rolls of large diameter and relatively small width, one of which is fixed and the other moving in slide blocks. The pressure required for comminu- tion is applied via the sliding roll by a powerful hydraulic system. The comminution takes place between the rolls under high pressure in the bed of material by nipping and compacting. The top feed size-depending on the rolls diameter -may be as coarse as conventional secondary crusher feed and the product is a compacted cake containing a high amount of fines created by micro-cracking. The amount of fines depends on the pres- sure (grinding force) applied. Operating results show that even in wet griding circuits capacity increases at downstream connected grinding mills of up to 100010 can be accomplished with an interconnected POLYCOM machine and energy savings of up to 25070 may be achieved depending on application. POLYCOM can be used in existing grinding plants for low-cost upgrad- ing of capacities but also as an advanced alternative to conventional crush- ing and grinding equipment in open or closed circuit configuration. A single industrial size 2.8m roll diameter POLYCOM machine may be fed with top feed size of up to 200mm and produce a finish product as fine- grained as known from rod and ball mills but with less energy consumption. Meanwhile, the POLYCOM high pressure grinding roll has established itself world-wide in the cement industry and is now entering the mining industry. POLYCOM machines are currently designed in industrial standard sizes of 1.0m to 2.0m rolls diameter and drive units of up to 2400 kW. This paper includes: principles of high pressure grinding, main fea tures of the POLYCOM machine, results of tests on various materials including Australian gold and copper ores carried out at the POLYSIUS research centre in Germany. Some examples of industrial applications of high pressure grinding will also be presented.

Jan 1, 1988

By Bhattacharyya A. K>

The Pemali Open Pit Mine is situated in a small island called Bangka in Indonesia. It produces approximately 165,000 m3/year of tin ore with an average grade of 3.67 kg/m' of tin from a primary deposit. The deposit occurs at the rim of a granitoid intrusion within sedimentary beds. The rock formations, all extremely weathered, and the overlying alluvium, are exposed to a rainfall exceeding 3m/year. Serious slope stability problems are experienced at the mine, despite using overall pit slopes of 20¦-29¦, the latter resulting in a stripping ratio of 4:1. This paper outlines a computer based back analysis of a major slope failure involving some 250,000 m' of material which occurred on the west wall of the pit in February, 1984. The findings from the analysis, together with other information, are used to examine the stability of the east wall of the pit, where tension cracks developed later. The results indicate that the large influx of water was the most significant cause of such slope stability problems and a more intensified water management programme would be beneficial.

Jan 1, 1989

By Paley N, Cameron A, Townson P

Although blasthole deviation is a problem which can seriously affect blasting operations, there is little practical emphasis on controlling this deviation and no practical emphasis on understanding its practical behaviour. The most common way of dealing with it involves tight control over drill set up and surveying hole paths. The surveying might involve simple collar location and inclination measurement to estimate the hole's actual path. At best, some operations routinely survey hole paths after all holes in a stope have been drilled. In addition, although there is an expectation that holes will deviate, there is no planning for this behaviour in order to reduce its impact on the blast. Design decisions are invariably made with the assumption that holes are straight. If and when surveys reveal problems it is possible only to adjust charging and initiation to 'work around them'. In extreme cases the drill might be recalled to fill in gaps. The lack of planning and the lack of understanding are doubtlessly linked.A model is presented that will predict the expected path of a drill hole. By knowing how a selected few holes deviated it is possible to make a good estimate of the deviation of other holes in the same rock mass. After minimal calibration the model can be used to increase the amount of information for a given amount of surveying or the amount of surveying can be reduced while maintaining the same level of knowledge of blasthole deviation. Equally important is the ability to plan for the deviation in future drilling through altering the initial collar angles or drilling from different locations. It is the authors' hope that planning for hole deviation becomes as much a part of the design process as planning for detonator delay scatter and explosive performance variation.

Jan 1, 1992

The accuracy with which block estimates are perceived is obtained by calculation of the kriging variance. This is dependent upon the model chosen for the semi-variogram of the deposit. For an extensive series of spherical semi-variograms the changes in the kriging variance resulting from various degrees of misassignment of the relative nugget effect are investigated. The results are reported as contour maps of percentage change in kriging variance as a function of the range and relative nugget effect of the true model.

Jan 1, 1985

Recent data contributions to New Zealand Mesozoic terrane geology confirm the consensus interpretation that New Zealand grew by the progressive addition of material by plutonic and accretionary processes along the Gondwana margin. The data also (1) emphasise the discontinuous but inter-related nature of these processes of continental growth, (2) better establish a direct Gondwana correlation of the Western Province and probable Gondwana provenance of at least some of the Eastern Province, (3) suggest specific times and places when passive or strike-slip rather than subduction regimes are recorded along the south Gondwana margin, and (4) potentially lead to interpretations emphasising parautochthonous rather than far- travelled relationships between many New Zealand terranes.

Jan 1, 1995

In 1985 a 2.5-tonne top blown rotary converter was installed in the silver refinery at Cominco's Trail Operation to carry out the final cupellation of burndown metal to Dore metal. The furnace is fired with an oxygen-natural gas lance which is capable of achieving a variety of furnace conditions, varying from reducing to highly oxidizing. Reaction rates are about 4 times greater than using conventional cupel furnaces. The faster reaction rates improve productivity and reduce in-process precious metal tie-up. The furnace is also used to reduce litharge slag for bismuth recovery.

Jan 1, 1989

For the purpose of this paper the Otago Region is that covered by the Otago Regional Council. This area, like other South Island Regions, has a river system starting in the Mountains and are all gravel bed rivers. The gravel from these rivers has been the major source of aggregate in the region since the development of the province began. The majority of the aggregate is a mix of greywacke, schist and quartz, which will be referred to later with its production problems. The region has been broken down into various areas.

Jan 1, 1992

Pulverised coal firing was pioneered in the cement industry prior to the turn of the century. Ash from the coal is absorbed into the mix in the kiln and replaces secondary materials. With high purity limestone coal with high ash content can be used. Fuel cost is a major part of the total manufacturing cost. Cement plants are thus quick to respond to fuel price changes and will use low grade fuels if there is a price advantage. Combustion conditions in a cement kiln differ markedly from a boiler. Flame length is determined by air/fuel mixing but because of fixed secondary air conditions this depends on primary air momentum. Volatile content has some effect on flame length but this can be offset by coal fineness. Much of the heat for cement production is for limestone calcination which is a low grade energy requirement. By allowing long residence time in separate direct fired vessels which then feed the high temperature kiln the energy of materials such as oil shale, tyres and lump lignite can be utilised.

Jan 1, 1987

Hindustan Zinc Limited has successfully installed an In-Stream Analysis and Process Control System in the flotation section of the Balaria Lead-Zinc concentrator at Zawar Mines. The system comprises In-Stream Analysis to continuously monitor lead and zinc levels in feed, concentrates and tailings streams, field instrumentation for reagent distribution and flotation cell level control linked to a central Distributed Control System for supervisory control functions. An intensive training scheme was conducted by the system supplier for concentrator metallurgical and instrumentation engineers. Since commissioning of the system in April 1989, Hindustan Zinc has enjoyed the benefits of improved lead, zinc and silver recoveries, improved concentrate grade control and reduced reagent costs.

Jan 1, 1991