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Best practice in environmental performance is a principle now increasingly and rapidly transferred around the globe. This matches both the greater rigour of environmental standards and the growing uniformity and `internationalisation' of standards for environmental management. There is no difference in the application of Normandy's environmental policy anywhere in the world.Normandy Mining is developing an Environmental Management System (EMS) which will satisfy:ò the need for technical excellence and best practice;ò the need to demonstrate `due diligence' in any jurisdiction;ò the need for financial statements and for insurance to reflect real world requirements for management of risk and liability.

Jan 1, 1997

Dilution in underground coal operations can be underestimated by up to five times during feasibility studies, with disastrous economic consequences. Every one per cent of stone waste introduced can reduce an in situ specific energy of 25 MJ/kg by some 0.25 MJ/kg and increases the abrasiveness of the run-of-mine coal. Where a wash plant is not in place, penalties imposed for not meeting contractual specifications alone can amount to some $A 1 million per year. This paper presents a method for monitoring, reporting and ultimately controlling dilution in an underground coal mining operation and presents the dilution trends from a continuous miner/longwall mine over an eight year period. The overall dilution level for the mine can be back-calculated by comparing the run-of-mine coal quality to the predicted in situ, undiluted quality. However, this will not identify the actual contaminant types, areas of the mine responsible for the dilution and the reasons for the dilution. This additional information is essential for controlling dilution to acceptable levels. Quality and horizon control using existing sampling information is generally only adequate for longer-term control purposes, and is not suitable for monitoring mining-induced dilution. The cost of close-spaced surface drilling to collect the information necessary for short-term control is prohibitive, particularly for deeper mines. However, much of this data can be collected through underground channel sampling and horizon control measurements taken during continuous miner development and longwall extraction. The mine runs the risk of not meeting contractual quality specifications and of increased equipment wear if this additional information is not available and the sources of dilution cannot be controlled. The information can also be used to plan longwall extraction heights on a short-term scale with resulting improvements in productivity.

Jan 1, 2003

Exceptionally weak ground, usually associated with faulting, unanticipated groundwater pressures or flows and exceptionally high stress concentrations are some of the hazards which confront the underground excavation engineer. One or more of these hazards can seriously delay or even halt a tunnel or mining project, and methods for predicting these hazards are urgently required, particularly for projects involving high speed drill and blast or tunnelling machine excavations.This paper explores the current availability and the potential for the development of tools and techniques for the prediction of these hazards. It is concluded that systematic and automated geological data collection and interpretation represent the most promising avenue for development. It is suggested that there is room for the use of expert systems in which the computer is used to assemble and organize practical underground excavation experience into an interactive decision making system.

Jan 1, 1985

By Wright J. K

In recent years the production of steel from directly reduced iron ore pellets has ex- panded rapidly. However continued growth will depend on an adequate supply of suitable raw materials for the various commercial gaseous and solid reductant processes now in operation. Al- though at present Australia does not produce pellets primarily for direct reduction, there is an increasing awareness of Australia's potential role as a supplier of high grade ores for export and/or domestic use. The properties and quality requirements of iron ore pellets made specifically for directre- duction (DR) are reviewed and the laboratory techniques and test methods used at the CSIRO Division of Process Technology for the evaluat- ion of potential DR feedstocks are described. At the present time most of the evaluation tests for DR pellets are extensions of those de- signed for existing blast furnace (BF) burdens. In the case of some physical parameters such as cold compression strength, abrasion index and cold strength after reduction this extension is quite satisfactory. In the measurement of para- meters such as reducibility, swelling and stick- ing tendency, however, it is necessary to deve- lop meaningful standardized tests so that ores and pellets can be ranked for DR performance. To do this, data from the laboratory tests and from operating plants must be correlated.

Jan 1, 1980

By E E. Hall, C D. Taylor, D S. Yantek

Regular monitoring for methane gas is required near working faces in gassy underground mines where the potential for methane ignitions is greatest. However, high concentrations of methane can also accumulate outby the face where methane levels are monitored less frequently. Wearing a personal methane monitor equipped with an alarm could protect persons working in these outby areas from injury or death due to methane ignitions. The National Institute for Occupational Safety and Health (NIOSH) has conducted studies to evaluate methanometers that could be used as person-wearable monitors. For the present study, seven different person-wearable monitors that are not currently approved for underground use were evaluated. This paper describes test procedures used to evaluate performance of methane monitors that could be used underground for continuous personal monitoring of methane. The information in this report provides data that allows the reader to make side-by side comparisons of these instruments.

Jan 1, 2005

ABSTRACT- I Chemotrophic bacteria, capable of oxidising inorganic species such as Fe(II) and S(-]I) for their metabolic energy, have been known for many decades and interest in these bacterial species has increased since their ability oxidise auriferous arsenopyrite ores has been demonstrated. The rate at which bacterial cultures can oxidise a solid sulphide ore is of importance but a number of difficulties arise when attempting to evaluate this oxidative activity. The two major problems are counting the number of viable bacteria present in the reactor and identifying the types of bacteria that are active in both the solid and liquid phases. Enumerating the numbers of bacteria responsible for an observed change is necessary to compare the activity of different isolates. For selection and identification of bacteria during the development stages of a project, and for monitoring an operational process, the recognition of different species will be of importance. Methods for the taxonomic discrimination of bacterial species rely on observations, different culturing techniques, and the degree of DNA base homology between isolates. A method reported recently uses IR spectroscopy for comparisons between isolates. This spectroscopic method and its application is discussed.

Jan 1, 1991

Mr. Bradford said: - On assuming this chair, which has been oc- cupied by so many gentlemen of conspicuous ability, my first words must be an expression of the gratitude I feel for the honour you have done me in electing me to be your President for this year. When considering the subject matter of this address to you to- night, quite frankly may it be stated that for a long time I was on the horns of a very great dilemma, for while I could discourse on the modern political trend in relation to our industries at great length, it appeared to me that this was not the place for such a discussion.

Jan 1, 1987

By Partridge AC

In order to provide a'valid description of the performance of size classifying equipment it is necessary that a standard procedure be established for testing and for the subsequent expression of results. Such a standard would permit the valid comparison of alternative equipment and may provide a basis for the prediction of performance. An Australian Standard (AS 1634-1974) has been used as the starting point for an International Standards Organisation-(ISO) working group (of which the authors are members) charged with the preparation of an ISO Standard for the expression and presentation of the results of tests on coal size classifying equipment. The approach taken is applicable to all types of sizing equipment (cyclones, screens, dedusters, etc.) and should be suitable for adoption in the minerals industry as well as by coal preparation engineers. The background to the proposed Standard, is given,including a critical review of other frequently quoted performance measures, the procedures described in the draft are discussed, and an example given.

Jan 1, 1984

By B Cronin, M Gao, M F. Young

Fine grinding technology has become extremely important for Mount Isa Mines Limited in the last decade for flowsheet development for the McArthur River deposit and in rejuvenating the Lead-Zinc Concentrator at Mount Isa. Regrinding products with 80 per cent passing seven microns and 12 microns were required, respectively, for the McArthur River ore and the Lead-Zinc Concentrator at Mount Isa. Development of the ISAMILL, a horizontal stirred mill with a gross mill volume of 4000 litres (a net volume of 3000 litres), has been successful in delivering the required grinding product sizes with an energy consumption acceptable to a mining operation. The ISAMILL performance for processing both lead and zinc streams at Mount Isa is discussed in this paper, including the milling energy efficiency, the media wear and the size-by-size recovery data for one flotation process following the fine regrinding stage. The potential use of the ISAMILL technology at various phases of the mining cycle is also discussed.

Jan 1, 1998

By Wright S, Rogers L. J, Precious T. H

Brown coal and its char were investigated as substitutes for petroleum coke in the manufacture of anodes for Hall-Heroult cells. The char, which had been densified by several techniques, was made into compacts with various binders and the anodic consumption determined during electrolysis. The results were an improvement on previous work, but the anodes still fell short of acceptability for use in aluminium smelters because of intractable microporosity. Some options for future development have been discounted.

Jan 1, 1986

The metallurgical testwork program is generally the most important critical path item for the completion of a bankable feasibility study and hence can become the critical parameter for financing of potential mining projects. This paper presents generic detailed testwork programs suitable for bankable feasibility studies for a gold leaching and polymetallic flotation study. The design of the metallurgical testwork program for each of the two differing processes is discussed and the critical factors that effect the selection of the testwork programs are highlighted. The importance of the metallurgical testwork results in predicting the metal recoveries and cash flow prediction for the project is presented. The detail of the testwork programs costing is broken into activity based methods based on the laboratory and management hours/costs, such that generic rule of thumb costing guidelines can be generated. The scheduling, costing and importance of the metallurgical testwork program to process feasibility studies are discussed in this paper.

Jan 1, 2000

The Circum-Pacific is defined to include back arcs and continental areas of volcanism. Volcanoes must be regarded as dormant, if the time since their last eruption is less than about ten times the average interval between eruptions, even if they have not erupted for tens of thousands of years or longer. It is important to establish a complete history, over as long a period as possible, for varying volumes of eruptions. In order to assess risk, the average interval between eruptions should be calculated for each range of erupted vo4ume~, in orders of magnitude from about 10 m up to the maximum volume possible at each volcano. Eruptions are considered to consist of individual explosions, and are grouped into eruptive sequences, with the sequences grouped into overall cycles of activity. Frequency of eruption versus volume erupted is a linear relationship for most andesitic and basaltic volcanoes, but is often bimodal at rhyolitic volcanoes, 3 with a slower eruption rate above about 10 km. Worldwide, during the last 7000 years, there have been three known e~uptions with volumes of ejecta of > 100 km , a9d, since 1638 A.D., 7 with volumes > 10 km , and 48 with volumes > 1 km . Average recurrence intervals are about 71 years for eruptions of > 20 km , 39 years for those of > 10 km , and 7 years for those of > 1 km . Rough esti- mates can be made for larger volumes erupted. Mean intervals in the Circum-Pacific are about twice the length of those for the world as a whole. During the last 400 years, about 61% of the world's eruptions of > 1 km3 have taken place in this region.

Jan 1, 1987

The necessity for agreed project outcomes, which are in accordance with client needs, and the subsequent requirement for a unique approach to managing project implementation is discussed. Reasons for appointing a separate project team to manage a project are established. The selection of a project manager, based on the services they can provide and on their characteristics, skills and management style, is discussed. The consequences of selecting the wrong project manager are explored. A broad overview of the requirements for the project team is provided. Criteria for the selection of team members, and the role played by the project manager in this selection, are discussed. The levers that drive `on-time and on-budget' projects are discussed in terms of the project's vision, goals, controls, and incentives.

Jan 1, 1997

By Childs G, Ritchie IC

This paper describes the principle and operation of small hydrocyclones for use in the coal, minerals and other process industries. The principles for selecting a hydrocyclone for an application are also discussed. Typic- al uses and installations in various industries are described.

Jan 1, 1984

By Smith I, Gowan M

With the advent of increased environmental regulation and high penalties for non-compliance in many countries, there has grown a need for all industries to assess their risk with respect to environmental compliance and consequently develop management systems which ensure environmental compliance and sound environmental practice. The need to better assess and manage environmental risk has developed rapidly as legal and financial penalties have increased for inappropriate management of the environment. The mechanism that industry has developed to manage risk is through the use of environmental management systems. These environmental management systems are generally based on the principles of total quality management. For example the British Standard BS7750 (Specification for Environmental Management System) shares common management system principles with ISO 9000 quality management systems. The same trends of increased environmental regulation and higher penalties for environmental impairment are now evident in Australia where environmental management systems are now being introduced. With increased penalties for environmental impairment and greater responsibility of managers and directors, environmental management systems are likely to become even more common in Australia. This paper describes some of the influences directing environmental management within the Australian industrial and mining environment, describes the elements of an environmental management system and relates these to the mining industry.

Jan 1, 1994

The current quantity of rejects from coal beneficiation in Australia represents 20 to 25% of raw black coal production. Approximately 80% of the rejects are derived from coarse processing for particles in the 200mm to 0.5mm size range. The safe and enviornmentally acceptable storage of coarse coal rejects is of interest to coal mining companies. Additional public benefit would be derived from the utilisation of a waste product as a source of fill material for civil and mining engineering applications. BHP Engineering has taken a leading role in the design for storage and utilisation of coarse rejects from two mines associated with the Broken Hill Proprietary Conipany Ltd. The tailings dam at Stockton Borehole Colliery (N.S.W.) is to be raised and a study by BHP Engineering has shown that coarse rejects are suitable for the formation of the supporting embankment surrounding a compacted clay core. Transportation and storage of coarse rejects at the Thiess Dampier Mitsui Riverside Mine (Moranbah, Qld) is achieved by a conveyor leading directly from the coal preparation plant to a discharge stacker on the crest of the rejects stockpile. Production of coarse rejects was higher than anticipated for the initial dump design. BHP Engineering has completed a review of dump design with emphasis on safe operating conditions for the conveyors and stacker system. Data on the geotechnical properties of coarse rejects from Australian coal mines are presented. Coarse coal rejects are a material which should not be considered as waste, but as a potentially valuable resource for many future applications. Appropriate engineering design for the storage and utilisation of coarse rejects would result in an improved environment and economic benefits for the Community.

Jan 1, 1987

By P Bethune

Back Creek is a tributary of the Condamine River. It flows in a northerly direction across the existing Commodore coal reserves. The diversion of Back Creek was proposed to minimise sterilisation of the reserves. The approval process required a Waterworks Licence application, under the Water Resources Act 1989 (Qld), for the construction of a stream diversion channel and floodway. The diversion was designed using the æreference reachÆ approach, which mimicked existing properties of Back Creek. The following design standards were developed for the diversion: the diversion corridor width was 500 m; the diversion geometry was specified for both the low-flow channel, and the floodplain; material properties were specified for both the low-flow channel lining and the diversion bund; compaction standards for both the low-flow channel and floodplain were set; and the diversion rehabilitation included a riparian corridor and pasture land with clumps of native trees and shrubs. The following performance criteria were developed for the diversion: velocity regimes were replicated for the design events considered, in an attempt to avoid increasing the diversion flow velocities in comparison with the existing creek flow velocities; sediment transport calculations indicated that no significant change in sediment transport was expected within the diversion; overburden settlement estimates for the spoil placed in the corridor were summarised, and will be monitored throughout the construction process; geotechnical stability of the proposed Eastern Pit Buttress and the diversion bund configurations was confirmed; and groundwater impacts were assessed. Construction techniques, monitoring and further investigations are also discussed in this paper.

Jan 1, 2003

This paper describes the MillMapper technology developed for condition monitoring of liners and other operational parameters in grinding mills used for mineral comminution, by presenting a case study of its application. MillMapper provides maintenance engineers, operations managers and process and plant metallurgists with quantitative, accurate and reliable condition monitoring data for informed decision making regarding the maintenance and metallurgical aspects of such mills. MillMapper uses calibrated laser scanners for the capture of three-dimensional surface representations inside a mill during a shutdown so as to determine shell, feed and discharge liner thickness at a resolution of several million data points, a procedure that nominally takes five minutes to complete. Once several data sets over time have been collected inside a mill, MillMapper can be used for liner wear, liner wear zone, liner weight, ball charge volume, ball charge weight and intelligent profile tracking over time. Liner tracking in combination with site defined reline and failure criteria and with throughput tonnage data is utilised for change out prediction of each separate liner segment type.

Jan 1, 2008

By Gibson I, Somerville J

Three main confined aquifers occur in interseam sediments beneath the planned excavation for the Loy Yang Brown Coal Open Cut. Sub-artesian groundwater pressures occur in all aquifers necessitating dewatering to prevent excessive seepage and depressurisation to prevent heaving of the open cut floor and batter instability. Reduction of water pressures in coal joints is also required to maintain coal face stability. This paper describes the depressurization and dewatering strategies, investigation for and installation of pump bores and groundwater observation bores. Approximately 5000m of drilling is carried out annually for dewatering at Loy Yang and both cable tool and rotary flush drilling methods are utilized. The cabletool method is used to obtain accurate samples for laboratory analysis, whereas rotary flush methods are used for speed and for installation of the larger diameter pumping bores. A method of re-establishing pump bores after partial excavation during mine development has been successfully developed with large cost savings. Trials are also being conducted with pre-collaring of deep bores with rotary methods then sampling the aquifer strata with a cable tool rig.

Jan 1, 1988

By M Roche, W J. Huxley

Finding a balance between practical and acceptable groundwater management, and providing for the needs and impacts of mining developments remains a challenge. The changes that accompanied the recent implementation of water reforms have provided greater flexibility for the water manager and greater certainty for the resource user. However uncertainty associated with understanding of complex aquifer systems, balanced against providing for the needs of mining developments, the rights of existing water resource users and expectations of the broader community have not diminished the conflicting issues faced by water resource managers and resource developers. Licensing under the Water Act 2000 provides the regulatory link with the taking of water for water supply purposes or as a consequence of the mining activity. This paper outlines key elements of sustainable water resource management involving certainty of access to water and adaptive environmental management that are delivered through conditioning the water licences issued for the particular mining development. Implementation of this approach is illustrated through a case study involving the BHP Billiton Cannington Mine in North West Queensland.

Jan 1, 2003