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Many persons hold the opinion that the metal indus- ries are fortuitous and that the occupation is one of sordid toil, and altogether a kind of business requir- ing not so much skill as labour. But as for myself, when I reflect carefully upon its special points one by one, it appears to be far otherwise. So wrote Georgius Agricola in 1556. He could have been espousing the sentiments of an indus- trial archaeologist investigating mining sites in 1986. South Australia has a very rich legacy from its industrial past-especially in the area of its mining history. Industrial archaeology, which is part of the broad field of archaeology, is concerned with the material and documentary remains of this industrial past. This includes the products and processes of manufacturing, industrial, technolog- ical and engineering activity and their relation- ships to people and the environment. `Archaeology' immediately conjures up the image of excavations in Greece or Eygpt. Excavation however is only a part of archaeological methodology. Industrial archaeology utilizes documentary historical rec- ords combined with field survey techniques (both above and below ground) to create a composite picture of the past. Interest in our recent past has burgeoned in Australia in the last few years. This interest manifests itself in many ways-the unprecedented popularity of Australiana and col- lecting, the plethora of Australian historic films, the growth of the National Trust, local historical societies and genealogical research. Fortunately these trends have been reflected in academic and legislative circles. Various univers- ities, institutes of technology and colleges of advanced education run courses in aspects of cul- tural resource management and conservation of the historic environment. These courses are com- prised of archaeology, architecture, geography, his- tory, materials conservation, museum studies, and national parks management and planning.

Jan 1, 1987

By Hyde L. J

Blasting is one of the available technologies to be employed in underground excavation systems. In many instances it can be the only technology which is suitable. The recent moves towards more mechanised working systems is resulting in a reduced awareness of new blasting practices and technologies on the part of many excavation engineers. Recent developments in blasting systems can be utilised to significantly improve operating efficiency, reduce total cycle times, better comply with regional environmental constraints and reduce the total cost of underground excavation. Blasting is and will remain, a very adaptable and exciting alternative which is far from boring.

Jan 1, 1987

By McCarthy J

In both the U.S.A. and Canada regulations concerning the reporting on mineral resources and especially ore reserves have been established. The regulations are virtually identical for the two countries with the main exceptions being who is franchised to write the report and how the various reserve categories may be used in reports to the public. Both countries divide ore reserves into "proven", "probable" and "inferred" categories. "Proven" reserves are those for material for which tonnage is computed from dimensions revealed in outcrops, trenches, underground workings or drill holes and for which the grade is composed from the results of adequate sampling. "Probable" reserves are those which are less well defined than "proven" while "inferred" reserves are generally those which may exist through geological and geophysical interpretation. The AusIMM/AMIC draft guidelines as proposed for use in Australia define more rigidly the ore reserve categories into "proved" and "probable" terms, which can only be applied following a full and favourable analysis of economic, mining, metallurgical, marketing and sociopolitical factors. If the ore reserves are not supported by this analysis they are placed into a "resource" category. Proper application of this proposed Australian model could prove useful when dealing with grass-root prospects or mining properties in the pre-feasibility stage. Combined with competent reporting, use of the proposed guidelines should ensure standardised and more verifiable analysis/valuation of a company's mineral assets.

Jan 1, 1987

By Fukuichi K, Matsukawa H, Nakagawa M

The Myojin Tunnel, located on the Shikoku Expressway being constructed by the Japan Highway Public Corporation, is 3,770 m long with a cross sectional area of 80 m2. Kajima Corporation, the contractor for the northern construction section of this tunnel, adopted here its newly developed "mini-bench" method of excavation. The objectives of this method were 1. to be able to perform all tunnelling operations using the whole cross sectional area of the tunnel under any ground conditions, and 2. to be able to vary the length of the mini-bench within the range of 0 to 7 m according to ground conditions. In order to achieve these objectives, original, sophisticated equipment was developed and employed in the work. One of the newly developed machines is a special jumbo, a hydraulic crawler jumbo with five rotary type booms. This machine is capable of accommodating variation in the length of the mini-bench accompanying changes in ground conditions and is equipped with a special mechanism by which the positions of the booms can be controlled by means of hydraulic cylinders. Also developed was a shotcrete robot for use with the mini-bench method which has the control board near the shotcrete nozzle for close control of application.

Jan 1, 1987

By J. W. Oberholzer

The use of computers in the South African coal mining industry has increased during the 1980s. Applications at mine level commenced in the financial and personnel areas of payroll systems, mine accounting procedures and staff record keeping. More use is made now on mines of technical programs for purposes such as mine planning and mine survey calculations. The Coal Mining Laboratory of the Chamber of Mines Research Organization has provided, for a number of years, a service to Chamber member collieries in regard to the application of technical computer programs. Programs presently in use for simulating production procedures and conveyor belt transport systems are described. In addition, reference is made to the collection, storage and analysis of data concerning the performance of continuous miners over a period of eight years. More recently a computer program for the simulation of the cutting action of continuous miner cutting drums has been developed. The use of this program to assist with drum design is explained. The fact that many requests to make use of the programs are received from collieries is an indication of their acceptance by industry. Their interest in running the programs themselves on their own desktop computers has led to the need to convert the software for microcomputers.

Jan 1, 1987

Petroleum exploration in the Australian arid zone has been proceeding at an ever-increasing pace, subject to financial fluctuations, since the 1960's. The impacts of petroleum exploration in the arid zone are less than they would be for corresponding operations in. e.g. a forest area: in this context, Australia is fortunate in that its major petroleum producing (and prospective) , basins are offshore or in the arid zone. In addition. the other major sources of impact in the Austrlian arid zone, namely pastoralism, tourism, and rabbits, tend to be concentrated around areas of particular conservation significance, whereas petroleum exploration is not. Despite this, the cumulative impacts of exploration are sufficient to have caused concern to government regulatory authorities and some sectors of the general public. Exploration is now subject to a range of environmental constraints with various degrees of legal enforceability. To enable exploration to continue without public opposition, the industry, and government agencies charged with regulating or supervising it, must demonstrate that the net benefits of exploration exceed net costs, including environmental costs. One particularly simple and cost-effective technique for increasing the net benefit/cost ratio of exploration is to reduce the net environmental costs by minimising and mitigating the impacts, both primary and secondary, of seismic acqisition. This is best achieved by a combination of preventive and restorative techniques: careful line positioning and low-impact (or zero) line clearance, coupled with simple rehabilitation of bladed lines. Line clearance without bulldozer blading - e.g. by rolling or simply pegging and trafficking, perhaps with tracked rather than rubber-tyred vibroseis - is one promising approach currently coming into use. Rehabilitation by grading soil banks ("windrows") back on to bladed tracks, though not yet in widespread use, has proved very successful in the limited areas where it has been applied to date.

Jan 1, 1987

By S. C. Greeff

At ISCOR the quantitative determination of the structural properties of coke is done with a Leitz-TAS Image Analysis System. A reflected light microscopic image of a coke sample is converted into a binary image and stored in computer memory or on hard disc. By means of mathematical and stereological techniques the system can transform the images electronically. A lightpen can be used to determine the sequence of these operations. TASIC, which is based on BASIC language, is used as the program language on the computer. The majority of the programs are written by the user to ensure satisfactory results for specific studies. The computer controls the whole system, including the movement of the microscope stage, focusing, transformation and measurement of the image and data processing. The computer is also applied for establishing statistical correlations between the structural and other coke and coal parameters as well as for graphics and predictions of the coke structure. Factors affecting the structural properties of coke are discussed and conclusions are drawn.

Jan 1, 1987

By George W. Poling

Designing optimal placer gold recovery plants requires a detailed knowledge of the size, shape and surface physical characteristics of the gold particles and the host alluvium in the pay gravel, sand or clay. Results of a recent pilot-scale study of the quantitative performance characteristics of riffled matted sluice systems are presented. For the appropriate non-coherent pay gravel-sand with medium-flat gold, simple sluices can recover gold at greater than 85% efficiency down to 100pm diameter. Alternatives to simple sluices are presented and discussed briefly.

Jan 1, 1987

By Alexander I. Feldman, Michael S. Kucker, Robert A. Robinson, Harvey W. Parker

An extensive geotechnical monitoring program was used to assess ground and liner behavior, provide input to a Disputes Review Board, and verify design assumptions during construction of the Mt. Baker Ridge Highway Tunnel along I-90 in Seattle, Washington. The stacked-drift tunnel liner was constructed with twenty-four 2.9 m diameter concrete-filled drifts forming a semi-flexible compression ring, followed by excavation of the 19.4 m diameter soil core. Instrumentation data was used for monitoring hillside stability, liner deflections and loads, impacts on adjacent highway tunnels, for back analyzing soil properties, and for helping to limit construction-induced settlements to about 6 cm.

Jan 1, 1987

By S. J. Anderson

To deftne the capabilities of a nonexplosive excavation concept, the Bureau of Mines conducted reduced-scale laboratory tests of a mechanical excavation tool called a rock splitter. The splitter investigated was capable of applying combinations of radial and axial loads to rock when placed in a predrilled hole. Experiments conducted with the tool in concrete, limestone, and granite proved it capable of excavating all three materials. Break geometry in these three materials was the same, which encourages the prediction of performance in all rocks. The design of the radial-axial loading splitter's feather components significantly affected the tool's performance. It appears the design of this in-hole component should be tailored for the rock to be excavated.

Jan 1, 1987

By Kevin R. Burns, William A. Depree, John J. Jansky

This paper presents some of the work associated with the reduction of employee exposure to diesel and blasting contaminants at an underground salt mine. The purpose of the paper is to outline the procedures recommended in resolving the problems associated with these contaminants. The first stage consists of a complete mine ventilation survey. The purpose of the survey is to identify any problems in the mine. The survey consists of air quality, air quality and ventilating pressure measurements taken throughout the mine. After completing the survey, the information is analyzed to identify problem areas and the possible causes. All available solutions to reduce the levels of contaminants are then explored and evaluated for feasibility. The PSU Mine Ventilation Simulator is then used to accurately simulate possible changes to the ventilation system. These ventilation projections are a useful tool to illustrate to the company and union personnel the possible benefits of various ventilation changes. This paper will illustrate the phases involved in making important and sometimes expensive ventilation decisions. Through the cooperative efforts of MSHA, company and union personnel, the levels of contaminants have been reduced by approximately 200 percent. As a result of these ventilation improvements, the company can now safely increase production approximately 25 percent.

Jan 1, 1987

By William Mayrsohn

INTRODUCTION The net smelter return (NSR) calculations made on various smelter-refiner alternatives, is usually done by taking the gross metal value less metal deductions, smelter-refiner charges and transportation-insurance costs. An important further step in the calculations is the financial charges imputed by refining time, transportation delays, to the time gold is returned (if tolled) or paid for if bought by the refiner. Metal that is priced in advance of payment also requires a forward premium that the mine may or may not be getting. This is a hidden cost that is often omitted from the calculations. Segmentation of each of the above costs are vital to see where improvements can be made through negotiations, better choice of metal pricing or transportation alternatives. BASIC NSR CALCULATIONS SMELTER-REFINER CHARGES Payable Metals - Treatment Refining Charges: Since these can vary from one smelter to another, the effect of a $25 per ounce price increase/decrease should be calculated and kept in mind. This effect is compared to differences in refining/treatment charge and a total smelter/refiner cost on a cost per ounce of dore, gold, or a dry ton of concentrate. Transportation - Insurance: Research has to be done on transportation alternatives perhaps with some assistance from the smelters, railroads or trucking companies. For dore, the U.S. postal service is viable and inexpensive. For railroads, deal with the regional office ie., B&N El Paso, if production warrants regular bulk shipments. Spot rates tend to be higher. A small mine producing concentrates usually goes to the nearest smelter due to extremely high transportation costs. Here is where a refiner can help. Insurance-Quotes for rates on dore/ concentrates are easily obtainable, but the mine has to shop for the best rates. Your insurance broker is the best source of this information. Differences between Mine and Smelter/Refiners Metal losses can be caused by the following: - Concentrate dry weight differences caused by moisture determination or faulty scales (often at the mine). - Sample bias by poor preparation practices on either side ie., grinding of the sample removing gold; or a poorly mixed concentrate. Dore bullion has no such difficulties.

Jan 1, 1987

By John M. Anderson

This paper examines the methods available to improve climatic conditions around a deep, high production longwall district of a British coal mine using results from a computer model. Such methods include the provision of increased ventilation quantities, the application of refrigeration, the reduction of heat input at source and the use of alternative ventilation systems. An approach to the solution of a climatic problem is explained with reference to other coal mine contaminants and a cooling strategy for deep high production British coal mines is described.

Jan 1, 1987

By W. N. Hamilton

British Columbia is geologically favourable for a rich variety of industrial mineral occurrences. Some have been produced for years, others overlooked until recently. Major production occurs for asbestos, gypsum, limestone, magnesite, silica and sulfur; lesser production for a dozen others. For several of the minerals, potential is much greater than existing production. New production opportunities exist also for diamonds, niobium and REE minerals, fluorspar, kyanite, nepheline syenite, talc, and several others. Alberta, though geologically less diverse, also has many industrial minerals. Limestone, salt and sulfur have the major production; clay and shale, silica, sodium sulfate and a few others lesser production. Opportunities exist for expanded production, and for new production in heavy (Ti -Zr) minerals, formation brines (Ca-Mg-I-Li), and gypsum.

Jan 1, 1987

By I. Clauzier

"A new method of managing electricity to reduce costs andimprove profits is discussed. Before taking steps to better manage electricity, it is essential to understand the terms peak demand and energy and their effect on an electrical bill. Knowing how electricity is presently used in the plant is the important first step. This goes beyond knowing how much electricity is used at each time of day, the individual contribution of every plant process to the total plant load must be known. At this point, each process is ranked according to importance to production in order to identify possible savings opportunities. These improvements can then be implemented by simply improving operations or in some cases, through the use of an automatic control system. IntroductionIn today's competitive environment, controlling costs is becoming increasingly important. All costs associated with operation must be controlled in an effort to improve competitive position. Electricity is a cost component that can and should be managed.Although the term management can mean different things to different people, the intent is always the same: to make the best possible use of existing resources, whether labour, equipment or electricity.The simple approach to managing electricity presented in this paper consists of four steps.I. Understand Peak Demand and Energy. It is essential to understand the terms, peak demand and energy and their effect on your electrical bill.2. Know Your Present Electrical Use. The present use of electricity in the plant must be known. This goes beyond simply knowing how much is used at each time of day, to accurately knowing how each process is contributing to the total plant electrical load, and ultimately to the electrical bill.3. Identification of Savings Opportunities. With this information, energy savings opportunities for reducing the electrical bill and improving profits can be identified.4. Implementing Improvements. Having identified areas of potential savings, improvements can then be implemented in order of their significance. This could be a matter of simply improving operations, or in some eases may mean the use of an automatic control system.These four steps can result in significant dollar savings."

Jan 1, 1987

The proportion of coal production from underground operations in Queensland, is likely to increase in the future. A portion of this increase will come from mines working under farming areas. The degree of compatibility between underground coal mining operations and farming is examined. Two case histories are considered in detail. These relate to farming areas in the Moura and Emerald districts. Mining the Moura, area has been undertaken for the last two and half decades, while in the Emerald area, large scale underground coal mining is currently being planned. Interference to watercourses and water harvesting programmes, damage to crops, and ponding in cultivated areas have been experienced in mining areas. With expansion of underground mining in farming areas, the principle areas of likely conflict are the effects of surface subsidence on irrigation and erosion control structures. Other potential problems that may arise in particular circumstances include reduction in availability of water for harvesting, pollution, surface cracking and damage to surface structures. Finely textured soils and erratic and violent rainfall patterns make farming in central Queensland particularly vulnerable to severe soil erosion unless strict precautions are taken. Soil erosion control is an essential part of farming. Contour banks are used to ensure that runoff velocities are suitably low. Where steep slopes are encountered, grassing is the most effective way to prevent erosion.

Jan 1, 1987

By Jeffery H. Stricklin

Jim Walter Resources operates five underground coal mines with longwall faces in operation in four of the mines. Due to high air velocities (1000-1200 fpm) needed for methane control together with the friability of the coal, dust control on JWR longwalls offers unique challenges. We have tested many innovative measures to reduce respirable dust concentrations on longwalls with varying degrees of success. These measures include the "shearer clearer" system, different drum water spray configurations, sprays on the longwall belt, stageloader and crusher sprays, wetting agents in the spray water system, and homotropal ventilation. Water infusion of deactivated horizontal methane drainage holes in longwall panels is now being evaluated. A study was completed in November 1986 where water was infused into two horizontal de-gas holes. Personal gravimetric samplers were used to measure respirable dust concentrations and showed a significant reduction in the infused zone. A more in depth study will be conducted. This paper will describe the dust control measures presently used on JWR longwalls, give the results of past studies, and discuss new methods proposed to control longwall dust.

Jan 1, 1987

Epicentres of recent shallow earthquakes in the region (3-12¦S, 126-150`E) were plotted to identify the various plate boundaries in the region, in particular the southernmost one marking the northern edge of the Australian plate. New and published fault plane solutions were examined to determine the style of faulting and state of stress along the Australian plate boundary. From east to west the boundary is first a subduction zone along the Solomon Islands, then a spreading centre across the Solomon Sea, a zone of compression and left lateral strike slip along the Papua Peninsula, almost pure thrusting across the centre of New Guinea and lastly left lateral strike silo through Irian Taya to the outer Banda Arc. The principal stress is very consistent, trending NW to NNW in a near horizontal plane, from the triple junction of the Pacific, Solomon Sea and Australian plates in the east to the Banda Sea in the west. Only along southern Solomon Sea plate margin which is a divergent boundary, is the stress different in type and direction.

Jan 1, 1987

The paper describes the design of the dilute medium and medium recovery circuits installed at the coal preparation plants at the Cornwall Coal Company's Fingal Mine, and the BP Coal Australia's Howick Mine. These circuits maximize the use of clarified water for rinsing to improve the mass transfer of adhering medium from the coal surface into the carrying liquid, and have been combined with the use of a two stage magnetic separator. The separator utilizes a conventional concurrent first stage and a counter-rotation second stage. This combination results in high medium recoveries during both normal operation, and start up and shut down phases when large quantities of medium can be lost from a conventional circuit. Overall losses using this circuit have been estimated to be, 200g/t, over a twelve month period. Further advantages in plant operation are also obtained, especially steady operating conditions in the centre-tube pump tank, lower slimes contamination of the product, and lower quantities of non magnetics trapped in the separator concentrates. The techniques are particularly suited to incorporation in circuits treating coals containing high percentages of sticky and difficult clays, as are found in the Walloon coal measures.

Jan 1, 1987

By J. H. Tylczak, R. Blickensderfer, D. J. Singleton

As part of its research on wear of mining and mineral processing equipment, the US Bureau of Mines evaluated the erosion-corrosion characteristics of 12 alloys in phosphoric acid waste water. Tests were conducted on 2- and 5-cm-diam specimen8 in 12- and 60-cm-diam ball mills by grinding phosphate rock in gypsum pond water with an initial pH of 1.6. For comparison, grinding tests also were conducted in tap water. Static corrosion tests in gypsum pond water also were carried out. For all alloys tested, the wear by erosion-corrosion was greater than the sum of erosion plus static corrosion. A low-alloy, high-carbon steel and a high-manganese, nitrided stainless steel were the most cost-effective materials

Jan 1, 1987