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In essence, these statements concur, However, management predominantly controls the organisation's communication environment (5), Consequently, the participation by employees in safety is greatly influenced by the quality of upward communication, (See section on authority for discussion on two way communica-ò tionò) Emotional survival contributes to the communications and it is said to occur as follows: -- We. aU tend to move towaAA 6.itw tLon,s which aid the achievement oj5 owc goa o and way {y/wm ones which testh ict achievement." Consequently, although the work force are prepared to contribute, they will not make the effort for long if management does not respond in deed. The Robers report includes the following statement; "Satiety and heat h at wank is a matte o6 e66ic,ient management. But it .L not a management pn.enogative. Wank people muht be encouAagad to pattiaipate úu.Uy in the making and movutoni:ng ob a/vua.ngements ban .6aJety and heath, at their. pace ofj wonk.t'(3) Attitudes dominate within this region. Emotional surviv- al is paramount. Management is the catalyst. They dominate the communication channels. Participation does not exist without two way communications and positive responses by those involved, Fault Doctrine. Eliminate faulty human behaviour. This concept lives with us as the predominant prior- ity of many safety programs. The concept is a drain on limited resources., Remember, malaria. At one stage this disease was believed to be caused by the mat or bad air emanating from persons whose profaneness or impious behaviour incurred such reprisal. Today, such a concept of malaria seems so ridiculous, (9)

Jan 1, 1979

There are three major human resource management activities which, depending on how well they are done, impact on the performance of people and therefore the bottom line. These are: ò recruitment; ò training and development; and ò performance appraisal. Most sizeable organisations would say they are involved in all three, but there are many more that would admit that their human resource management practices are limited to recruitment. If we concentrate on the organisations that currently undertake all three, we have to ask, `Are they using different systems/benchmarks for each activity, or is there congruence between the activities?'. Our experience is that most organisations use different systems/benchmarks. The end result is: ò one set of criteria to recruit staff; ò another to identify their training needs; ò and yet another set of criteria to measure their staff's Performance.

Jan 1, 1995

Neutralisation, normally using lime, is the most widely used method for treating high flows of acid mine drainage (AMD). Lime costs can be very high however. If carbonate sources could be used to achieve pH values above six, costs could be greatly reduced. For example, use of locally quarried limestone at Mt Lyell could potentially reduce alkali costs from about $A 3.5 to $A 1 million/year. Methods for enhancing the effectiveness of limestone and magnesite for neutralising Mt Lyell and Savage River AMD respectively have been examined through a series of investigations. Small-scale testwork found that the maximum pH economically achievable with ground limestone was about five, due to slow dissolution rates and surface armouring. The problems of surface armouring were greatly reduced by the use of crushed limestone or magnesite at high pulp densities (75 per cent solids w/w), enabling pH values >6 to be achieved in a practical time frame. The use of particle sizes in the range 6 mm and finer also reduces costs by avoiding the need for grinding, and reduces the problems of solid-liquid separation and solid recycling that arise if large additions of ground carbonate are used. Pilot scale tests were carried out using tumbling drum reactors with limestone and Mt Lyell AMD and a pulsed-bed static reactor with magnesite and Savage River AMD. pH values averaging 6.2 and 6.4 were achieved with Mt Lyell and Savage River AMD respectively. Approximately 80 per cent of feed acidity was neutralised. A preliminary engineering design and cost estimate has been completed on the pulsed-bed reactor and shows that the concept is technically feasible and, if results are confirmed, economically attractive. Further pilot testing is planned.

Jan 1, 2002

Esso Australia Ltd. operates a large natural gas producing system in the Gippsland Basin, supplying gas to the Gas and Fuel Corporation of Victoria, the State Electricity Commission of Victoria and several industrial customers. Gas reaches the Longford processing plants from three offshore platforms via a network of large diameter pipelines, which must be protected against the formation of ice-like hydrates. When gas production commenced in 1969, methanol was used to inhibit hydrate formation in the offshore pipelines. However, later investigations showed that the methanol was causing excessive degradation of molecular sieve in the onshore gas-processing plants. (Molecular sieve is used to remove water and H2S from the gas prior to further processing to remove heavy hydrocarbons.)

Jan 1, 1982

In order to maintain an accurate survey underground, it is first necessary to connect all shafts used for the transferring of the survey to the levels below by a precise surface survey.This has been achieved at Mount Isa by a careful triangulation survey with stations adjacent to those shafts most suitably located for transferring the survey below.The precedure used is described herein.The Weisbach triangle commonly used is obtained by reading to swingirig wires, the theodolite being placed in line with them as nearly as is possible. The surveyor at the surface places the wires in the shaft as far apart as the size of the shaft will permit, with sufficient space between the wires and walls to ensure their swinging freely. The far wire is fixed in position, while the near one is movable by means of fine adjusting screws to facilitate its being brought into line with the fixed wire and the theodolite. When this is done the surveyor at the lower level is advised by pre-arranged signals and the survey can then commence.The surface portion of the survey is simple; all that is necessary being to read the angle from the backsight to the wires, measure their distance from the theodolite, and keep a check on them throughout the survey to make sure that no movement takes place.The lower portion of the survey is more difficult, the surveyor first qf all having to place his theodolite as nearly as possible in line with the wires.

Jan 1, 1953

In six deep hard coal mines situated in the coal district of the Saar and Lorraine, Saarbergwerke AG produce annually 9 to 10 million tons of coal. The coal is either coked or fired in power plants. Comprehensive planning work is done for the producing coal faces, 15 stone drifts and 60 seam headings. The computer can assist in drawing up the short- and medium-term planning by taking over, on the one hand, work done so far by hand and by supplying, on the other, additional information. The computer can draw up time schedules, can do quantitative calculations, can draw up plans for the em- ployment of manpower, machines and other equipment, and can calculate cost and earnings. It is ensured that all part plans are always adjusted to each other. Because of the volume of work involved, planning in this form and extent becomes possible only by the computer. Especially with the periodical continuation of planning, the new system facilitates the work to be done. The ideas of the planning engineer are and remain the basis of all planning work and the computer gives him an aid to assist him with calculations, report writing and feasibility studies.

Jan 1, 1977

This paper describes several sources of external dilution affecting the stope walls during underground sub-level and bench stoping. Factors which control ground behaviour such as the geometry of the openings, the influence of geological discontinuities, stress re-distribution and blasting practices are discussed. Crown stope instability due to stress concentrations induced by changes in the excavation geometry, is discussed and the most efficient ways to sequence blasting within a stope are analysed. Effects of undercutting by blasting, blast damage in the near field and cut-off slot blast designs are analysed. The influence of dynamic loading on the exposed walls as well as the practice of blasting fill passes within stope crowns are discussed.

Jan 1, 1995

By Y Chen, G Xu, B Albijanic

High concentrations of airborne coal particles is the main reason leading to health and safety hazards in underground coalmines. Water spray is one of the effective methods to suppress coal particles in mine sites, but the use of plain water is not effective enough to capture coal particles. By adding surfactants, coal wettability can be improved which will increase the coal dust suppression efficiency. In this study, a modified sink test was employed to evaluate coal wettability in the presence of two anionic surfactants: sodium dodecyl sulfate (SDS) and sodium dodecyl benzene sulfonate (SDBS). Sink rates were calculated by measuring sink weight over test time. Different surfactant concentrations (0.01 per cent, 0.05 per cent, 0.1 per cent, 0.2 per cent and 0.4 per cent) and two types of water (tap water and deionised water) were selected to investigate coal wettability over three size ranges (0–38, 53–75 and 75–90 µm). The results show that both SDS and SDBS surfactants can lower the water surface tension and improve coal wetting performance. Sink rates increased as the surfactant concentration increased, and surfactant solutions prepared by tap water performed better than deionised water in enhancing coal wettability. Also, coal wettability varied for different coal particle sizes; the smaller coal particles were, the worse the wettability they possessed.CITATION:Chen, Y, Xu, G, Wang, R and Albijanic, B, 2017. Study on coal wettability for dust suppression in the presence of surfactants by sink test, in Proceedings Australian Mine Vent Conference 2017, pp 105–110 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

Of the world's total production of gold the largest proportion comes from the more regularly consistent ore bodies, but in the aggregate an important part comes from those which are often irregular, uncertain and small. These smaller ore bodies are often high in grade and, as the capital required to work them is not large, they appeal to people seeking a quick and profitable return for a small outlay.These small mining concerns cannot afford detailed geological and petrological investigations and mapping, so they are very often dependent on local knowledge and experience which admittedly may be of really great value.Nevertheless the absence of skilled guidance may not only cause good opportunities for intelligent exploration to be lost, but discourage the seach for other ore bodies.lVIining engineers in the course of their travels in the examination of mines often come across such cases and also others where problems of finding lost ore bodies have been solved by the man on the spot. As records of cases are valuable and useful additions to the knowledge of ore occurrences, the writer now proposes to describe one such case coming under his observation in recent years.It is that of a small mine, known as the Idaho, at the southern end of the famous "Golden Mile" at Kalgoorlie (see Fig. 1). This mine has been a small and very erratic producer ever since it was abandoned by an English company which owned it forty years ago. Except for one period of four years it has always been owned and worked by parties of co-operative miners and during its time has gone through a tortuous career. Although it has often...

Jan 1, 1938

Mine Dewatering for reoccupation of a flooded mine requires rehabilitation and recommissioning of shaft and sane level functions to provide safe efficient access, services and logistics, as well as securing connections with all exposed workings. The objective is the earliest secure reoccupation of the target depth horizon for minimum water pumping, consistent with an appropriate investment and optimum schedule of operating inputs to the dewatering, redevelopment, services and consolidation processes. Strategy must focus on recommissioning of relevant functions in the shaft and at stage pumping horizons, advance of logistics close to pumping and rehabilitation, management of the secured exposed workings. The progress must be systematic, sustained and integrated, and must be secured against risk and uncertainty. There must be a strategic capability to respond effectively, and manage interruptions to processes, conditions requiring higher or different resources, and contingencies which affect schedule, budget or risk profile for the continuing programme. Planning must aim to reduce or contain risk or uncertainty elements and contingencies, limit interruption frequency and severity, identify and provide the capability for efficient responses. It is appropriate to model and simulate the reoccupation analogous to a mine initial development production programme. Only minor changes to relationships and relativities of models for Capital works, Operations (Production and Development) and Services/Logistics are needed but the model for management of workings is more relevant than that for depleted workings in an operating mine because of the water and other transfers. An important difference is the unsteady state of operations which requires probabilistic modelling of availability and utilization of equipment and processes.

Jan 1, 1988

Unnamed early prospectors panned gold from creeks drain- ing the Great Dividing Range in the early part of 1851. The first publicised discovery was credited to Edward Hargraves near Bathurst in New South Wales later in 1851 and during the ensu- ing gold rush, prospectors rapidly made discoveries elsewhere in New South Wales and later across the border in Victoria. Reference to the attached graphs of gold production indicates that for much of the first 100 years, gold production came from the easily worked and readily discovered shallow alluvial deposits, many of which were located in the creeks draining mountainous regions of Victoria, New South Wales and Queensland (Fig. 1 and 2). As these deposits were exhausted, prospectors turned their attention to outcrop lode deposits which led to the development of underground mining techniques and a significant boost in over- all gold production. With the discovery of the rich Golden Mile lodes in Kalgoorlie in 1893, gold production increased signifi- cantly and peaked around the turn of the century. At that time, the enormous potential of the great Witwatersrand deposits in South Africa had only just been appreciated and for a few years, Australia led the world in gold production (1855-1863 and again in 1903). Underground mining continued in the Eastern Goldfields area of Western Australia, the Bendigo-Ballarat region of Victoria and in northeast Queensland. Very few of these operations continued beyond the Second World War, except the larger producers in the Kalgoorlie region where recovered grade had dropped to about 6 g/t Au. By the early 1970s with the gold price fixed at US$35 per ounce, most of the operations were shut down as labour costs escalated, with only the low cost bulk mining operation at Mt. Charlotte and the high grade reefs at Norseman continuing in Production.

Jan 1, 1988

By Anderson DR, Tassell G

A major environmental impact study carried out in the sand dunes of eastern Cape York used image analysis of remotely sensed data to both select sites for ground investigation and categorise the different ecological units present. The approach adopted was particularly suited to the type of environment in question and allowed a high degree of quantification, at a high level of confidence, at costs several orders of magnitude less than conventional Methods.

Jan 1, 1987

The accurate calculation of ore reserves is one of the most important functions under- taken at a potential or operating mine. In recent years there has been a trend towards recommending more and more complex techniques for the calculation of reserves. However these are not always necessary and many improvements could be made by the use of all potential data and a heavier geological input. An ore reserve should be the result of geological not mathe- matical or engineering reasoning. All ore reserve estimates are wrong and the important thing is to.recognise why they-are wrong and to take action to minimize the errors. Geostatistics and other complex mathematical techniques may appear to answer all our needs for ore reserve accuracy but there are many drawbacks, not least of which is the communi- cation gap which may develop between the operator and both management and production Personnel.

Jan 1, 1979

By R J. Goldfarb

Reduced intrusion-related gold deposits have become a new, low-grade, large-tonnage exploration target during the last decade. The best recognized examples of such deposits are recognized throughout the Tintina Gold Province of the northern North American Cordillera. Because such examples may have many features in common with orogenic gold deposits, such as anomalous Bi, W and Te, low salinity and CO2-rich ore fluids, and a spatial/temporal association with igneous rocks, confusion and controversy have now become commonplace in classification of many gold deposits formed along convergent margins. The best discriminators of IRGS are likely to be their: +        regional location in deformed shelf sequences on the inboard side of a series of accreted terranes and within terranes that also contain important tin and (or) tungsten deposits; +        local spatial association of gold ores with cupolas and contact aureoles of relatively reduced, alkaline-leaning, and volatile-rich plutons; +        post-deformational timing of gold deposition; +        extremely low sulfide content (commonly <1 vol %) of ores within igneous bodies and the outward zoning, through proximal skarns and to distal base metal-rich veins, from the causative pluton; and +        low grades (<1 g/t Au) of auriferous sheeted vein systems in pluton cupolas.

Jan 1, 2005

Although bismuth mineralization is spread widely through the Lachlan Fold Belt in New South Wales, broad grouping of the various deposits can be effected on the basis of geographical and geological (age and type of associated rocks) affinities. As a result, significant concentrations of bismuth can be recognized in the Mid-Western granites, Cobar-type ore, the Yass Silurian acid volcanic belt, and the Albury, Bega, Braidwoodand Bathurst districts.In these deposits bismuth generally occurs in minor amounts associated with molybdenite, wolframite, scheelite, cassiterite, chalcopyrite, galena, magnetite, pyrite, arsenopyrite, and native gold. From this group of minerals three broadly defined associations can be recognized.I. Bi-Sn-W-Mo2. Bi-Au( -Te)3. Bi-Pb-Cu(-Au)There may be some interchangeability of these metals, as instanced by occasional Bi-Cu-W-Mo mirleralization, but pyrite and/ or arsenopyrite are usually prominent in all associations.The first two of these associations occur mainly in the form of narrow quartz veins rarely averaging more than O· 3 per cent Bi, although there is often a marked enrichment in ferruginous material in the oxidized zone.Most of these veins occur within or adjacent to granitic rocks of varying ages (principally Silurian or Devonian), although Bi-Au mineralization tends to be related to more basic igneous activity than the Bi-Sn-W-Mo association.The latter is also occasionally developed in pipes, usually coarse-grained and richer in bismuth (as at Whipstick, the principal mine in New South Wales with a production of 343 tonnes of the metal), or in lower grade, but probably larger tonnage skarn deposits. The bismuth-base metal association occurs mainly in Silurian acid volcanic sequences and may also form low grade but large tonnage deposits, such as is possibly developed at Cobar.

Jan 1, 1973

By Robson W. D, Irwin D. A

In November, 1932, an investigation of silicosis was undertaken at the, McIntyre Porcupine Mine, Schumacher, Ont., atfer a discussion of the problem with Sir Frederick Banting and his, staff. As a result it was decided to carry on dusting experiments with animals at the mine in a manner that would duplicate as far as possible actual industrial conditions.At that time 50, guinea pigs were placed in the crusher nouse tunnel of the mill where a considerable quantity of fine dust, containing approximately 35 per cent., of free silica, was being constantly produced. These animals lived in this atmosphere for periods up to one year, and, while on autopsy large amounts of dust were found in the lungs, not a single case of silicosis had developed. These negative results suggested, among other things, that the mine gases might be a predisposing factor in the production of silicosis, and the results of this investigation led us to undertake the study of the hydrogen-ion concentration of the condensate of the atmosphere, both in the mine and in various sections of the mill.The C02 combining power of blood serum on a series of 400 miners was also studied at this time. While these results were inconclusive, the variation in the hydrogen-ion concentration of the condensate between the surface and underground atmospheres encouraged us to investigate the effect of neutral, weak acid and alkaline solutions on the solubility of silicious materials. Gye and Purdy were the first to point out that the chemical reaction and not the physical presence of silicious material was responsible for the production of the fibrosis in silicosis. This work was investigated by Gardner and Cummings who showed that the tissue reaction to quartz was definitely proportional to the size of the particle. They found that 1-3 micron particles of quartz produced an acute proliferative fibrotic response while the 10-12 micron particles produced only a foreign body reaction up to a period of three years. It is accepted that the dangerous silica particles retained by the lung are under 5 microns in diameter. We assumed that if the solubility of the silicious material retained in the lung could be reduced sufficiently by the addition of some non-toxic element or compound the usual fibrotic respohse would be modified. We found that the addition of certain compounds to silica would reduce its solubility in the beaker to a slight extent. But these compounds, when mixed with quartz...

Jan 1, 1945

By S Shipard

Filters are used in water treatment and hydrometallurgical process plants for objectives such as generating a dry spadable solid, pumpable high density slurry or high purity filtrate. The priority objective of every polishing filter, sometimes also termed clarifying filters is high purity filtrate and these are found in many diverse industries and even different applications within the same industry.To generate a high purity filtrate, process designers have the choice of many different polishing filter products, but in reality very few polishing filters are based on fundamentally different filtering concepts.This paper reviews the technology merits of well-known and the more recently developed polishing filter products and aims to assist metallurgists and engineers with the selection of an appropriate polishing filtration technology for pregnant liquor filtration and other process applications, plus a guide to best practice.CITATION:Shipard, S, 2013. Polishing filters for mineral processing plants, in Proceedings MetPlant 2013 , pp 118-125 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

The hematite deposits of Quadrilßtero Ferrffero (QF) are hosted by the Proterozoic itabirites of the Itabira iron formation (Harder and Chamberlin, 1915). These deposits are widely distributed at QF and include the hard hematite ore bodies. However, considerable variations in ore structure and texture can be observed. A preserved banding and lamination in the thin bedded, compact hematite ore, apparently reflects the original layering and/or the prominent foliation of the partly or completely replaced itabirite. The structure of the hematite ore deposits varies from almond shaped, rootless, to bedded bodies, both concordant with the main foliation, and to mesoscopic veins and irregular bodies. Hematite ore textures, which depends on the structural characteristics of the deposit, may be grouped into four main types:thin bedded, laminated and banded; micaceous, foliated and schistose; brecciated; and compact/massive. Thin bedded ores occur in the western, central and subordinately eastern portions of QF, while submicaceous, micaceous and schistose ores are predominant at the eastern part. Brecciated ores exist mainly at the western part and subordinately in central QF. Structureless, compact hematite ores may be either related to the brecciated hematite or occur as isolated bodies at central QF. It is suggested that a synkinematic, acid and oxidant, metasomatism during metamorphism, under a ductile regime, was responsible for the hard hematite ores of the types 1 and 2, and a static, subsequent, hydrothermal, regional metasomatism, under brittle regime resulted in the formation of the types 3 and 4. The common texture present in the all ores is the ubiquitous magnetite porphyroclasts replacement by hematite. Quartz and other silicate minerals are also substituted by hematite. Muscovite, tourmaline, talc, chlorite, apatite and kaolinite have been recognised in the hard hematitic ores. Apparently that mineral association denotes different equilibrium conditions of formation.

Jan 1, 2002

The theory of declining optimimum cut-off grades is more than 25 years old, but for a number of reasons it is still not widely used in industry. A lack of faith in the veracity of estimated grades is not in itself a reason to abandon any attempt to optimise cut-off grades. The use of declining cut-off grades has been thought to cause high-grading, but in fact this is only true if an artificially high discount rate is used in the calculations. Perfect application of an optimum cut-off grade should ensure that only ore generating more than a minimum net return is mined, and that as much as possible of the ore capable of generating that return is mined. Therefore differing mining costs in different parts of some underground mines necessitate local modifications to cut-off grade. Optimisation of cut-off grade is of necessity an iterative process. Integration of that process into a feasibility study need not be excessively time-consuming. A number of approximations can be made to speed the optimisation (any attempt to achieve a high level of accuracy is probably doomed to failure by a lack of precise cost and price projections). A procedure is outlined for optimising cut-off grade during planning of a typical underground mine.

Jan 1, 1991

By T N. Little

The author contends that geoscience is presently under-utilised in the rock fragmentation by blasting process. Before we can set standards in this area, the following is required: mine geologists need to gain a better understanding of the blasting process and the blasting team needs to obtain a better appreciation of geology. Both groups need to be informed of what can be done to improve blasting outcomes, why it is necessary and how it can be achieved. By working closely together, both the geoscience toolkits and blasting expertise can be applied and focused on priority blast sensitive issues, with potential to improve mine economics and safety. Finally, and ideally, mine geologists need to take a leadership role in raw rock mass data collection and data management, and invited to take an active role in rock mass related behaviour data collection, integration and presentation.This paper attempts to provide insight into all these prerequisites for setting a new standard for collaboration and mutual learning in this strategic opportunity area. The potential for blasting to leverage downstream processes is highlighted. Blasting objectives and blast design principles are introduced along with the required rock mass related inputs. Some hazardous geological materials and environmental conditions are described, along with how they can affect operational complexity.Four case examples are used to illustrate the need for closer liaison between geology and blasting professionals. The first related to grade control blasting, aims to demonstrate how a blasting geology approach can add significant value. Case example two demonstrates how geological models and bench face analysis can assist with fragment control. The third and fourth case examples involve an overview of two case studies where timely geological and geotechnical knowledge input and intervention into blasting activities may have reduced losses due to blast initiated open pit slope collapses.CITATION:Little, T N, 2017. Geoscience input into blasting operations – let’s set a new standard, in Proceedings Tenth International Mining Geology Conference 2017, pp 375–384 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017