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The Carnilya Hill Mine, a joint venture project between Western Mining Corporation Limited (WMC) and The Broken Hill Proprietary Company (BHP), is a nickel sulphide deposit being developed by the Kambalda Nickel Operations (KNO) of Western Mining Corporation. Seven months elapsed from the time a decision to proceed with the project was taken until the first ore production. During the first month of operation a new KNO record for decline development was set. Equipment used includes an electro- hydraulic drill jumbo, 4 cubic metre front end loaders, and 35 tonne haulage trucks.

Jan 1, 1981

By Luke K. A

Pressure on production at New Zealand China Clays has led to the development of a dewatering control loop for fine halloysite china clay. The development was based on the analysis of data from the automation of plate and frame filter presses. The analysis of the data has led to process changes, and the ability to quickly solve dewatering problems. As a result of control in the dewatering circuit press times have reduced on average 117% and output has increased proportionally.

Jan 1, 1989

By Swift D. G

For some time the Electricity Trust of South Australia (ETSA) has been investigating the application of new mining methods and equipment to minimise the cost impact of the steadily increasing depth of mining brought about by the 20¦ dip of the coal seams at the Leigh Creek Coalfield. Exhaustive examination of all suitable mining systems showed that highly mechanised systems involving belt conveyors displayed no eco- nomic or operational advantages over shovel and truck methods. However, the configuration of the Leigh Creek coalfield allows for two quite different approaches to mining by shovel and truck. The current strip mining method involves removing overburden from the highwall in 60 m to 200 m wide strips to progressively expose the coal down dip, and requires all waste to be hauled to the surface. The alternative ter- race haulback method involves opening a boxcut to full depth at one end of the coalfield, then mining the full section along strike and placing the spoil in the mined out area. On a strictly economic basis, the latter is clearly advantageous, but the former has significant less tangible advantages. In deciding between the two methods ETSA is faced with the need to examine the applicability of each method under a wide range of possible future demands on the coalfield, and to assess the importance of many intangible factors.

Jan 1, 1989

By Williams P. A

Tailings dams constructed by the upstream method have traditionally been built using the sand fraction of the tailings, which has automatically provided a relatively permeable embankment material, and helped provide the necessary drainage conditions which are a pre-requisite for safe and stable dam construction using this method. This paper discusses some recent trends which have resulted in proposals to use impermeable material in place of the sand fraction as the embankment material, both for the starter dam, and subsequent lifts. The consequences of these types of decisions on the overall stability of the dam are illustrated, and the need for continued monitoring of pore pressures in the tailings as the dam is raised is emphasised.

Jan 1, 1992

This paper discusses why Argyle Diamonds adopted thickened tailings disposal in 1985 and how the system was developed over the next seven years. A wide ranging review of the thickened tailings disposal system and the tailings deposit it was producing was carried out during 1992 and 1993. The results of that review led to the abandonment of thickened tailings disposal at Argyle because of serious concerns about the stability of the resultant tailings deposit. The exposure to the risk of liquefaction and an assessment of the consequences if this happened to the thickened tailings deposit are shown. The criteria for selecting the new tailings disposal strategy are then described. The final section of the paper discusses the management strategies that have been put in place. These are designed to: ò reduce the risk posed by the thickened tailings deposit to an acceptable level; ò safely store tailings to the end of mine life; ò produce a land form that can be decommissioned to the satisfaction of Government regulatory bodies.

Jan 1, 1996

This paper examines the interplay between longwall support design/geometry features, operational controls and geological features on ground response. Experience from several investigations is used to demonstrate the influence of factors such as longwall support capacity and geometry, setting pressure, coal seam strength and stiffness, tip-to-face distance and hydraulic supply and control system parameters on longwall ground response. These factors are then used to outline the requirements on key controls such as retreat rate and cutting height and their influence on allowable roof convergence. The ground response curve concept as a means to provide graphical representation of longwall support and strata interaction processes is presented. The approach was developed to address the requirement for a practical longwall support evaluation and selection tool that can take account of support load influences such as changes in roof geology or cover depth. An example of the comparison between single pass longwall and top coal caving in a thick seam environment is given to demonstrate the influence of the various factors discussed.

Jan 1, 2005

Optimisation and sensitivity analysis of final pit limits is now an accepted procedure for open pit planning studies. Tools to assist the design engineer in an underground metalliferous mine to make optimal choices for the selection of major development, stope geometry and cut-off grade analysis have not been available. The engineer has had to rely on experience and a limited analysis of design alternatives. A new tool called the `floating stope' has been developed to define the optimal (boundary) limit for material that can be economically extracted by underground stoping methods. The method is analogous to the `floating cone' method of open pit optimisation. The geology and mineralisation are modelled as a regular or subcell block model. Included in the model are structural and geotechnical features, and any previously mined out areas. Inputs to the procedure include the minimum stope dimensions, cut-off grade, stope head grade, and the way in which dilution is to be calculated. The optimisation procedure can be directed to maximise ore tonnes, grade, contained metal or the economic (dollar) value of material mined. The procedure can be applied at each stage of mine evaluation and design to assist with preliminary resource appraisal, selection of stoping methods, and detailed mine design. As with open pit optimisation procedures, manual intervention by an experienced engineer is required to produce practical and detailed designs. This practical design should follow the optimised design as closely as possible. The paper outlines the algorithms used in the definition of the stope envelope, and describes the analysis and results of several case studies where the optimisation procedure has been applied.

Jan 1, 1995

Don Hausen was a pioneer in the field of quantitative mineralogy. Methodology that he developed at Newmont almost 40 years ago is still employed today, only the technology has advanced. Petrographic methods were stressed with an emphasis on alteration, mineralisation and paragenesis. Methodologies employed by Don on the Carlin deposit were applied to developing the Carlin Trend by helping to work out lithology and structure, which ultimately led to the discovery of deep high-grade deposits. Quantitative methods used by Don on San Manuel, Copper Creek and Superior, Arizona were applied to the development of the Batu Hijau Deposit in Indonesia. Advancements in technology since DonÆs time have made the mineralogist much more efficient. Manual measurement of peak heights off of strip charts for semiquantitative XRD has been replaced by software that does Rietveld refinement and whole pattern fitting. Hand contouring of XRD data has been replaced by digitised data incorporated into geologic models. Optical point counting, which would take a dayÆs work to process 1000 points, has been replaced by automated SEM methods where 20 000 points are possible in an hour. The use of the optical microscope remains relatively unchanged, and still remains as Don emphasised the æeyesÆ of mineral exploration. However, the information can be relayed much more quickly with digital image capture and electronic data transfer. Don insisted on becoming involved in projects at the grassroots level and supporting the project through mine closure. This made the mineralogist a liaison between exploration geologists, mine geologists, metallurgists and mine engineers. The methodology that Don helped develop continues to provide invaluable support to Newmont geologists and metallurgists worldwide today.

Jan 1, 2008

Mining has long been an important activity for the people of Australia. The Aboriginals used rocks and minerals in their culture many thousand years before European settlement. It was not until 1840 that silver-lead ore was discovered in the Mount Lofty Ranges, and developed as Australia's first metalliferous mine.

Jan 1, 1995

By Howell IJ, Kirsopp R

In June/July 1981 Mount Isa Mines Limited was confronted with a crisis situation in the crushing operation of the Lead/Zinc and Copper Concentrators. Three crusher mainframes developed serious cracks in the upper rim area. The type of cracking indicated that major failure of these mainframes could be imminent. Operational crushers could not be sensibly inspected and it was therefore assumed that more than three mainframes were seriously cracked. The crisis was averted as described in the following text.

Jan 1, 1978

The on-going technical developments to enhance the productivity and cost effectiveness of large blasthole drills incorporate many of the blasthole drilling operating experiences garnered over the past half century.Those experiences have shown in part that on a drill unit with good quality structural elements the higher the percentage of the electrical and electronic components designed into the product, the higher its productivity and the lower its operating cost.

Jan 1, 1992

By Buizen M

The results of calibration trials conducted on parachute stoppings under a recently completed NERD&DC grant are presented. Applications of parachute stoppings, for rapid regulation and control of ventilation networks are described including use in mine recoveries, sealing sections and rescue work. Parachute stoppings are one of a series of non-rigid ventilation control structures specifically designed for quick installation in emergency situations, for use in high production/rapid advance areas and areas suffering roof-floor convergence.

Jan 1, 1988

By Dundon P

The Broken Hill Proprietary Company Limited (BHP) is Australia's largest company with widespread commercial interests ranging from steel productin to minerals, oil and gas recovery. While these interests are worldwide, the Company operates or is partner in more than 30 Australian mining ventures. BHP Engineering (BHPE) is the in-house consultant to BHP but is also the largest consultancy in Australia available to general industry. Australian Groundwater Consultants Pty Limited (AGC) is a large, independent consultancy offering specialist services in all aspects of water resources, waste management and environmental engineering, both in Australia and overseas. AGC is particularly well regarded within the mining industry and has a considerable record of providing solutions for mine water related issues. By drawing on the extensive combined experience of AGC and BHP Engineering, this paper will summarize some of the unique ways in which water interacts with and impacts on mining operations in Australia, particularly in matters such as: Slope Stability Drainage and Dewatering Production Cost (Transport, Drilling, Blasting, etc) Water Supply Water Management Tailings and Waste Management Environmental Issues. The paper will also illustrate the cost benefit of providing major engineering works for reduction in total mining cost. It will be shown that, through advance planning and close interaction between outside experts (ie consultants) and on- site personnel, very significant operational cost savings can be made while at the same time achieving a safe and responsible mining environment.

Jan 1, 1988

By S Youds

The backfilling operation at Olympic Dam mine supports a 9.8 Mtpa underground Long Hole Open Stoping (LHOS) operation. It involves a combination of Cemented Aggregate Fill (CAF), surface rockfill and underground rockfill. The fill material is introduced from the surface via boreholes into the top of the stopes. Due to the deleterious effects of the dust and the thickness of the atmosphere in the stope it is not possible to view the filling process either at optical or infrared (IR) wavelengths. The need for a means to measure the filling process is driven by the placement of both rock and CAF fill in the stopes. The large volumes and high relative cost of CAF makes the minimisation of CAF fill a business priority. Incorrect filling can lead to the sterilisation of ore reserve. The use of millimeter wave radar to view through the haze to give real-time data on the relative positions of the different fill masses is being developed as an in-stope fill monitoring device. This paper reviews the salient points of the technology and its potential use in the backfilling operation at Olympic Dam. The broader potential of this technology for use in the mining industry by æseeingÆ through water and dust laden environments such as that found in stopes and ore passes is also discussed.

Jan 1, 2002

Severe development difficulties were experienced soon after in-seam mining commenced at Appin Colliery in'1962. Thirteen years later no significant pro- gress had been made in overcoming some aspects of this development problem. Some success had been achieved in destressing roadways both in development and pillar extraction. Longwall retreat mining had shown promise of being highly productive but at an extremely high cost in terms of development requirements both in number of roadways and intensity of support in those roadways. No real advance was made in the problem of driving the first heading of a group of headings under conditions of apparently high stress in directions other than the preferred mining directions, although failure of the roof in this heading did seem to give easier work in the subsequent headings driven particularly if they were driven on narrow centres.

Jan 1, 1976

By N Harries

The management of risks associated with slope instability is an essential process in the safe and economic operation of open cut mines. The æslope stability radarÆ (SSR) has been developed to better manage those risks. The SSR can remotely scan a rock slope to continuously measure any movement of the face. The system can detect and alert users of wall movements with submillimetre precision. The high level of movement precision and broad area coverage of the rock face can allow for a better understanding of the geomechanics of slope deformation, including magnitude of potential failures and additional warning time of impending instability. Additionally, radar waves adequately penetrate through rain, dust and smoke to give reliable measurements, 24 hours a day. SSR systems have been deployed in many mines in Australia, Indonesia, Africa, Chile and the United States. Greater than 100 rock falls and waste dump failures (from several tonnes to millions of tonnes) have been monitored, and on every occasion precursor æwarningÆ movements were recorded by the SSR. This technology enables a radical change in the management of risks in open cut mining. This paper presents recent case studies of how the SSR technology has provided safety and productivity benefits to large open cut metalliferous mines.

Jan 1, 2007

The Merrill-Crowe process for gold and silver recovery yields a low grade concentrate containing high levels of zinc and copper. External refining charges and high transport costs prompted the company to establish itsown enrichment facility.The route chosen was a wet chemicaltreatment which converts the gold, silver and other metals to their chloride. This is achieved with hydrochloric acid and sodium hypochlorite. Gold is recovered from the resulting filtrate by cementation with copper.The solid residue from the gold process is washed and treated with ammonia which dissolves the silver chloride. Metallic silver is recovered from this solution, againby cementation with copper.

Jan 1, 1985

In the Massif du Sud ophiolite complex platinum group elements occur predominantly as ultrafine-grained inclusions of rutheniridosmine, laurite and iridosmine. These form primary inclusions less than 5 to 10 um in diameter within chromite in podiform chromitite fringed by dunite, and emplaced subsequent to solidification of the host harzburgite. There is no specific association with trace inclusions of transition metal sulphides. The crystallization of then: Ir. Os and Ru minerals may have occurred concomitant with hromite, perhaps related to more reducing conditions produced by crystallization of the chromite. The Ir, Os. and Ru show pronounced fractionation from Pd, Pt and Rh expected to be also present in the mantle source rock. The dunite shows evidence of metasomatic origin from adjoining harzburgite, and the possibility of selective crystallization of the Ir sub-group elements suggests that Pd, Pt and Rh may have been transported elsewhere.

Jan 1, 1989

By Linge H. G

The effect of the presence of ore pulp on the adsorption rate of gold on activated carbon has been studied. A substantial reduction in the rate occurs when the pulp is present. The reduction in rate appears to be caused by two effects: permanent carbon pore blocking by ore particles and temporary shielding of the carbon particle surface, slowing gold access to the carbon due to the physical presence of the fine pulp. There is no significant effect arising from the presence of a pulp viscosity modifier even for conditions when mass transport dictates the loading rate of carbon in clear Solution.

Jan 1, 1987

By J Krnmmelbein, T Raab

In Lusatia, lignite mining causes major disturbances on the landscape scale. Reclamation procedures are applied to recover the reconstructed landscape for different land use options. In this study we investigate soil physical properties of an agricultural reclamation/recultivation site directly after site restoration and the development of selected parameters within the first years after site restoration depending on varying recultivation strategies.The sandy substrates used for recultivation stem from depths of several meters. They are unstructured, free of recent organic matter and have high contents of calcium carbonate. During reconstruction and most of all during surface levelling with heavy crawlers, the substrate?undergoes high mechanical stresses. This leads to partly severe soil or substrate compaction, depending amongst others on substrate water content and mechanical stresses during site construction. We investigate the effect of different organic soil amendments, different crop rotations and partly subsoiling on the development of soil structure. We compare results of laboratory measurements directly after site construction before any reclamation measures had been applied to results we gained after three and four years of recultivation. The results show that after the earthworks are completed, the site is strongly heterogeneous in relation to mechanical stability, permeability for air and water, pore volume and bulk density. The results after three and four years show that the heterogeneity of soil physical parameters decreases. The selection of suitable crop rotations superimposes the affects of other reclamation measures, eg varying organic fertilisers or deep loosening.CITATION:Krnmmelbein, J and Raab, T, 2012. Reclaimed lignite mining areas A73 in Lusatia - Development of soil physical parameters of an agricultural site within the first years after site reconstruction, in Proceedings Life-of-Mine 2012 , pp 117-122 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012