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The Junction Reefs gold bearing deposit is situated on the Lyndhurst Mining Field in mid-west New South Wales. It is located within a triangle of three country towns namely, Blayney, Cowra and Canowindra, all three townships are approximately 25 km from the current operational mining leases. The district is well developed, having been settled for more than a cen- tury. However, being close to the Cities of Orange and Bathurst it is real- lised, instantly, that mining leases have been pegged, in this area, almost boundary to boundary. The lease patterns are, with few exceptions, those which had been estab- lished more than seventy-five years ago. These types of lease patterns may not assist the proper exploitation of a large district where there have been many discoveries of gold, copper and other metals.

Jan 1, 1988

By Barnett J. C

The arid and semi-arid region of Western Australia occupies about two-thirds of the State equivalent to an area of about 1.8 million sqkm. Groundwater demand in this area has historically been linked to the pastoral andmining industries commencing with the gold discoveries in the Eastern Goldfields some 100 years ago. Substantial increases in demand have occurred in the past two decades initially as a result of nickel discoveriesin the early 1970's and more recently the rapid resurgence of the gold mining industry. Mineral exploration and development in the Great Sandy Desert at Telfer (gold) and Kintyre (uranium) and in the Great Victoria Desert at MulgaRocks (uranium) has also been accompanied by detailed groundwater investigations.

Jan 1, 1988

By Baafi EY, MacKenzie -Wood P

An experienced and reliable knowledge of fire fighting procedures is necessary for mine emergency situations. Since experts in this area are scarce the technology of expert systems lends itself as a suitable component in the decision making process. This paper describes an expert system that is being developed for this purpose. The expert system. RESCUE. is a knowledge-based computer programme which incorporates the judgement, experience, rules of thumb. mine environmental conditions as well as human intuitions in the mine rescue operation. RESCUE makes decisions such as whether or not the affected area should be sealed.' whether or not rescuemen should be withdrawn, and which fire fighting agent is most appropriate for the situation. The IF..... THEN rules written in the VP-EXPERT shell contains antecedents and conclusions based on environmental as well as other conditions prevailing in the mine. For example, the CO/Oz deficiency ratio indicates the progress of heating; explosibility trends are given by varying flammable gases C CH4,H2,CO) in relation to oxygen concentration, and barometric pressure falls may affect explosibility by increasing CH4 content in workings. The interaction of such numeric-based rules with others rules reflecting the experience and judgement of the experts assist the system to arrive at its conclusions and subsequent course of action.

Jan 1, 1988

By Bicer N

Current problems in predicting sub-surface strata movement and fracture development due to longwall mining have highlighted the need for more accurate, dependable methods of physical modelling of rock mechanics problems which are beyond the capabilities of current mathematical techniques. Physical model studies of the caved zone above the working faces up to the base of a water source are of importance in attempting to understand changes in mass permeability due to induced fracture zones and the resulting ground water conditions. Turkey's most important supplies of coking coals are to be found within the hard coal resources of the Black Sea coast. Coal seams up to 9 metres thick, dipping at angles as steep as 90 degrees are being successfully mined at the Kozlu Mine. Since 1956, mining operations have been carried out under the sea in dry conditions. The undersea mining conditions of the Kozlu Mine have been investigated using scaled physical models constructed from artificial materials which satisfied necessary scaling requirements. Models representing the in-situ conditions were tested and the following extraction sequence was employed: 1. The Sulu Seam extraction 2. The Acilik Seam extraction (as two slices) 3. The Piric Seam extraction. The displacement of the fixed reference points were subsequently measured using a high precision photogrammetric technique and induced horizontal and vertical strains were calculated.

Jan 1, 1988

The search for an efficient and economic machine to excavate hard rock continues. Development of the Robbins Mobile Miner commenced in 1983 with the formation of a joint venture between Mount Isa Mines Limited and The Robbins Company. Construction of the machine ensued and preliminary trials to verify the cutting action were undertaken in the USA prior to transportation to and assembly at Mount I-sa where mining commenced in September 1984. Initially, the machine was used to develop the S60 Decline which serves as a combined access and conveyor drive for the Southern 1100 Orebody Ore Handling System.

Jan 1, 1988

By Sullivan TD, Redman PG

AND INTRODUCTION The Lochiel coal deposit, a large Tertiary soft brown coal deposit in the mid north of South Australia, is currently being investigated by the Electricity Trust of South Australia (ETSA) as a potential source of fuel for a base load power station. Feasibility studies indicated that the proposed dragline method of overburden removal was viable but economically sensitive to both highwail and dump batter angles. The unusual properties of the unconsolidated overburden sediments and the groundwater regime posed a number of intimately related hydrogeological and geotechnical questions which were addressed before and during the excavation of a trial pit. All strata at Lochiel are of soil strength, and artesian aquifers occur above and below the coal. From the initial evaluation of the deposit a number of hydrogeological questions were defined. These related to the rate at which the pore pressure in the silts is reduced by dewatering, the extent of the reduction in pore pressure due to prestripping, and the feasibility of dewatering and depressurising carbonaceous silty sand sequences. The site of the trial pit was selected to answer these and other questions from the basis of a detailed geological, hydrogeological and geotechnical understanding. The trial pit dewatering system simulated a full scale mine dewatering system and included ten pumped wells, twenty drainage wells, and nearly 400 monitoring instruments. It operated from September 1986 to June 1987. The excavation was carried out between February and May 1987.

Jan 1, 1988

Small mines exist because of a restricted deposit or a small market. With the right management at the present time the small mine can have lower total costs than larger mines. Charbon is an example of a small mine with a restricted deposit and a specialised product. The development which incorporates a unique rail loading facility and flexible coal preparation plant was achieved with a modest capital outlay and in record time. To remain competitive in future with large scale mines who seek increased production the small mine must achieve increased productivity through automation, higher speed equipment and a multiskilled workforce. Deregulation of the industry, scrapping the Coal Industry Tribunal and the Joint Coal Board would benefit small mines greatly. Management of a small operation also requires multiskills which need to be supported by outside help in the form of consultants and temporary staff. In the 21st century small mines will continue to provide a service to the market.

Jan 1, 1988

Congratulations on your considerable enterprise in securing the opportunity to have this international conference here in Brisbane - and congratulations on your success in attracting such a distinguished audience from so many nations, with such a broad selection of papers. It is a notable achievement that in the year in which Australia is celebrating two hundred years since settlers first came fran Britain, The Australasian Institute of Mining and Metallurgy is responsible for some ten major conferences, of which at least four are specifically international, or have a very strong international involvement.

Jan 1, 1988

By Giannini L. M

Optimisation techniques, based on the block model, for solving the optimum pit limit problem were discussed in an earlier paper. Of the available techniques the one based on graph theory proved to be the most attractive. In the graph theory model the vertices represent blocks and the arcs represent the mining restrictions. For large ore-bodies direct application of the graph theory method poses considerable computational and storage problems. Techniques for easing the computational effort by reducingthe problem size were introduced in an earlier paper. Further, significant computational savings can be made by exploiting the structure of the graph. This is done by building the graph up level by level and successively applying the graph theory algorithm to reduce the number of blocks. In building up the graph in this way one needs what is called a "search pattern" to indicate which arcs are to be added as new vertices are introduced. Moreover, as it is essential to keep the number of arcs to a minimum it is necessary to establish a "minimum search pattern".The problem of determining minimum search patterns for any block model and for any wall slope restrictions has not been considered in the literature.The objective of this paper is to present a complete solution to this problem and to discuss, through typical case studies, the application of the associated software developed.

Jan 1, 1988

The Canadian mining industry was in turmoil in the early 1980s. The post-war era based on reconstruction faded away after the high demands for minerals in the 1950s and 1960s. Also, the industry had the misconception that the demand growth would continue for ever but the rapid growth of resource industries in the third world in the 60s and 70s, resulted in worldwide production overcapacity. The Canadian mining industry eventually recognised the facts and took drastic action for cost control and innovation in technology. The cost control had an immediate effect on the survival of the industry but resulted in only limited incremental gains. The economic problems that the Canadian mining industry faced in the early 1980s can be viewed now as a blessing in disguise. It was realised that for the Canadian mining industry to survive in the 21st century further gains were possible only through innovative technology. This conclusion led to a flurry of activity to establish mechanisms and delivery systems for innovative technology in the mining industry. Despite the initial difficulties in accepting high technology in the mining industry, it is being used increasingly in mining operations and will make future mining operations unrecognizable to present day mining engineers. The concept of an underground mine without underground staff seems to be far fetched, but it is possible that mines of the 21st century will approach the concept of very few underground operating personnel.

Jan 1, 1988

By Biao Q, Mizuta Y

Thermal constants such as thermal con- ductivity and thermal diffusivity of rock and coefficient of heat transfer of airway wall are the most important characteristic values which decide accuracy of prediction calcula- tion. However, quality of rock is not homoge- neous and water content in rock varies with location and so, a method for in-situ measure- ment of thermal constants must be taken in. The method developed by us is to measure in- situ rock temperatures at two different depths from airway wall. It is simple and we found its accuracy is good enough in the engineering Sense.

Jan 1, 1988

By R C. Owen, M A. Ward

The paper describes the application of New Zealand's environmental impact assessment procedures to a proposed gold and silver mine in the North Island of New Zealand. The project is described and a summary is provided of the statutory permits or consents that are required prior to operation of the project. Emphasis is given to the requirement for environmental impact assessment and the preparation of a formal environmental impact report. The company's approach to impact assessment is described, with examples of how this assessment and the identification of management alternatives influenced the engineering design of the project. This paper was prepared as a contribution to a working session of the International Association of Impact Assessment VII Annual Conference, July 1988.

Jan 1, 1988

Projected cooling requirements for ERPM led to the first proposals for the large- scale use of ice for mine cooling in the early 1980's. Following successful research into ice conveying and ice melting a large ice plant was commissioned at Harmony in 1985 and a much larger 6000 ton per day plant is presently under construction at ERPM. A brief description of the mining project is given, followed by general descriptions of the surface ice plants and the ice conveying system, the systems for using the ice for mine cooling, and the control of the whole ice cooling System.

Jan 1, 1988

The sharp deterioration in Au~tralia'S ternn of trade in recent years and the accumulating national debt highlight the need for a restructuring of the economy which is highly dependent upon primary agricultural and mineral commodity exports (figure 1). Table I gives an indication of the value that can be added to raw material by mineral processing. Significantly higher value is added through downstream manufacturing. In 1987, the mining and rural sectors accounted for 47010 and 38010 respectively of total exports valued at $35,782 million (figure 2). The export contribution from minerals comprised $12,266 mil- lion from unprocessed ores and concentrates and $4,668 million from metals and processed minerals including some simple manufactures. Coal accounted for 450/s of total primary mineral exports. Iron ore and alumina are other important mineral exports, while gold and aluminium are major metal exports. (Figure 3) Australia's minerals are now traded in a much more competi- tive and oversupplied market in contrast to the 1960's and 1970's period which was characterised by increasing exports of largely unprocessed ores and concentrates. Since the early 1980's (I cI) resscd )ver~cas nutrkcts and km rununodlity liriccs ha~c hcen the product of excess capacity installed to satisfy a forecast high growth in demand which never eventuated due to the world reces- sion. During this period the emphasis on technology development was focussed on reducing costs through increased production effi- ciencies in order to maintain competitiveness.

Jan 1, 1988

By Weatherhead J, Grounds J

The Nabarlek Uranium Project located in Arnhem Land in the Northern Territory of Australia was a small high-grade deposit which was the first uranium mine brought into operation following the extensive Commissioner Fox Inquiries into uranium mining during the late 1970s. The operation is almost complete and decommissioning plans have been prepared. This paper reviews all phases of the water management and tailings disposal for the project and compares results with design predictions.

Jan 1, 1988

From statistics on general and electrical fatalities in the Australian mineral industry, it could be said that the present approach to industrial safety is irrational. Deaths are few and decreasing in number, yet spend- ing on occupational safety is large and increasing. State mine safety inspec- torates are being expanded and a National Occupational Health and Safety Commission was recently established. Recent data are analysed in the paper and mining industry fatalities placed in perspective with deaths in other areas. Cost effectiveness of different strategies is discussed along with social implications. Strategies found successful are described and others suggested.,

Jan 1, 1988

By Liu C. H, Juang Y. F

Coal/gas outbursts were one of the rather difficult safety problems faced in the coal mines of this Country, with coal fields characterized by frequent disturbances of folds, faults and pinch-offs. With average mining depth about 500m below surface, several such accidents occurred with up to 500 tonnes of coal outburst. In recent years, after a series of improving countermeasures had been undertaken, gas outburst accidents had been greatly decreased. The characteristics of gas outbursts in Taiwan coal mines include relating to coal petrography, mining depth and the other deformation forces. All these have been investigated, trying to determine the parameter of outbursts under natural conditions. The preventive countermeasures include predicting tests, de-stressing boring in coal seams, the emergency procedures during outbursts and certain improving options.

Jan 1, 1988

By W A. van der Westhuizen, Beukes G. J, Vermaak J. J

Large parts of the arid northern Cape Province South Africa are blanketed by Quaternary cal- crete under which potential base-metal ore- deposits may occur. In an attempt to examine the nature of the distribution of such ore-re- lated elements in a calcrete environment, calcrete and soil samples from the copper-nic- kel prospect at Jacomynspan and the copper- zinc deposit at Copperton were examined. Both deposits form part of the Namaqua mobile belt. CALCRETE GENESIS In Southern Africa calcrete is restricted mainly to the western two-thirds of the sub-continent, south of the latitude 17¦ S. Various models have been put forward to explain calcrete genesis and Goudie (1973) and Netterberg (1969a) give detailed discussions on this topic. The most popular model for calcrete genesis is one of pedogenic origin. McPherson (1979), Watts (1980), Wright (1982), Arakel (1982), Netterberg (1969a), Goudie (1973) and Multer and Hoffmeister (1968), amongst others, support the hypothesis of calcrete formation by carbonate precipitation from downward percolating calcium carbonate rich soil waters. Calcium carbonate is usually initially precipitated as nodules or grains which can develop to form more compact layers.

Jan 1, 1988

By Enichlmayr E

Lignin grouts are cheap and easy to get. They have some desirable properties, but they aag less used now because environmental pollution is often caused by Cr from the lignochrome component of the grout. Their usefulness was researched in an earlier paper on lignin as a grout from other viewpoints. A non-toxic grout FUL was made composed of furfural, urea and lignin. After initial tests, including tests by spinning regression design, some response equations in which FUL's properties are described were obtained. Optimum formulations have been established by using optimization methods based on response equations. The engineering quality was assured by formulations whose properties were measured in further tests. The mechanical feature of gelling sand was measured by means of triaxial tests. This provides a basis for using FUL grout in-situ. Finally, an in-situ experiment on FUL was completed successfully. The results were that cracks in stratum were filled or blocked, the gelling of FUL had high strength, and low permeability and consolidation were achieved.

Jan 1, 1988

The paper deals with the problems of grouting methods for fissured-porous rock. The paper describes design procedure, injection process patterns and hydrodynamic testing techni- que to plan grouting programs for fissured-porous aquifers. A number of case histories is given to illustrate the imp- lementation of developed methodology at various mining pro- jects.

Jan 1, 1988