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By D Elmo, M Scoble, Y Liu, B Klein, J Scholar, S Nadolski

A cave-to-mill study being conducted at the New Afton block caving operation demonstrated the potential for sensor-based ore sorting equipment to reject waste and improve the grade of feed to the mill. The lack of selectivity and potential for dilution entry associated with the block cave mining method results in many caving operations having to mine and process material that is below cut-off grade at certain stages of production. Online monitoring and bulk sorting systems have the potential to alleviate this problem and improve the productivity of caving operations while reducing energy and water requirements for each tonne of concentrate produced.As part of the cave-to-mill study, the suitability of a range of sensors, such as X-ray fluorescence and induction-type sensors, to sort mine production at the New Afton mine was investigated. Results showed that the discrimination of ore and waste can potentially be carried out by implementing surficial sensors into the material handling system. The study also showed that a combination of sensor outputs could be used to identify a certain ore type so that pre-emptive changes can be made in the mill to improve beneficiation performance. Overall, the outcomes of the study on implementing sensor systems at block cave mines are considered to be of significant relevance to a number of existing and future caving operations.CITATION:Nadolski, S, Klein, B, Elmo, D, Scoble, M, Liu, Y and Scholar, J, 2016. Investigation into the implementation of sensor-based ore sorting systems at a block caving operation, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 393–400 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

During the last two decades, restrictions on access to land for mineral exploration and development in Australia have intensified. State and Federal legislation relating to Aboriginal land rights, national parks, marine parks, wilderness areas and other conservation areas, the surface rights of farmers in New South Wales and Western Australia, national, State and world heritage, urban developments and acquisition of land by governments for other purposes have all placed limits on mineral exploration and mine development activity. More than 20% of Australia's land area is now either unavailable for mineral exploration or available only under severe constraints. Access to this land is denied at a significant economic cost to the Australian community. There have been few attempts to quantify this cost. More importantly these restrictions have developed on an ad hoc basis promoted by single interest government departments often with little regard for rational land use planning. The mining industry has embraced the community's conservation ethic and accepted that conservation areas should be set aside and that within those areas mineral activity should be restricted. In some cases the restrictions on exploration near areas of outstanding scientific, historical, archeological or scenic importance may amount to an effective prohibition. The industry has vigorously opposed the exclusion of mineral activity in conservation areas on purely emotive grounds, unsupported by scientific evidence and in disregard of land use potential, consideration of multiple use potential or consultation with existing or potential land users likely to be effected.

Jan 1, 1987

By Wu H. W, Just G. D

Australia's mineral resources boom in the two decades up to 1980 saw the establishment of about 25 new mining towns across the continent Quality housing and a high standard of community services were incorporated to attract a labour force for the major mine or mines i eing serviced. Town construction costs were high and were principally born by the private enterprise mine developer. There has been a change in the pattern in recent years and over 20 new mine developers have adopted a fly-in fly-out arrangement rather than construct new towns. Employees are drawn from a home base which is typically a large city, coastal community or established mining town and flown to the mine site for intensive work periods of about two weeks. The change has occurred for many reasons. Mining companies have been unwilling to support the high construction costs of towns, short life and smallermining operations do not justify a town, fast jet aircraft are available and there is a better perceived family lifestyle in established (coastal) communities. On the other hand reduced permanent development at new mine sites does not assist Australia's perceived need for decentralization. There have been questions as to the social problems which may develop from the artificial separation of the "breadwinner" from his family. The paper reviews a recent survey of the attitude of Australian mining companies employees, governments and unions to fly-in fly-out arrange- ments. The support for this approach is analysed and conclusions drawn that the concept is likely to be with the Australian mining industry for some time in the future.

Jan 1, 1991

By B Vorster, T Medhurst, A Huey

Roof conditions at Oaky North Mine can be prone to stress related damage and/or time dependent degradation. The ability to identify these areas prior to mining has proved challenging using traditional methods. To help alleviate this situation, a study was initiated to investigate methods for roof characterisation using geophysical logs. This involved the use of neutron log data to provide an indirect measure of the proportion of carbonaceous/micaceous laminae present in the immediate roof strata. Detailed analysis of the shale–porosity inter-relationships arising from this analysis provided a means to estimate the proportion of laminations for a given roof interval. This paper outlines the process and how it was used to improve the current GSR modelling and hazard mapping process.

Nov 29, 2022

By Hannan JC

Consent to develop and operate a new coal mine in New South Wales (NSW) will be conditional upon a number of environmental controls. In NSW, applications for any new major development associated with coal mining are determined by the Minister for Planning and Environment. The environ- mental conditions placed on the development consent, the coal mining lease and the approvals, and licences under the pollution control legislation amount to a substantial component of any new project's commissioning considerations. The nature, scale and location of projects and the principles of pollution control on which conditions of State Pollution Control Commission (SPCC) approvals are based have a considerable influence on project planning. The design, construction and operation of coal mines in NSW has been progressively modified over the past 15 years, to incorporate increasingly stringent requirements for environmental management. These requirements are in turn, a reflection of a greater community demand for environmental protection.

Jan 1, 1986

A zone rich in-fish debris in the Rolling Dow= Group in the sub-surface of the Great-Artesian Basin has been discovered a Further research has shoe i this zone to-be of very wide distribution in the Artesian Basin and to occur. at the base of the Ta?nbo .f ormati'on resting on the Roma forma-tion. The zone gives a very characteristic curve on the electric and' gamma ray logs and is thus an excellent correlation marker in the sub-surface over a very wide area. It is probably to be correlated sith.the Toolebuc member described from: outcrops east of Boulia. There .are apparent similarities between the Fishecale zone of the Great Artesian Basin in' Australia and the Fishscale sand of the Western Canada Sedimentary Basin.

Jan 1, 1962

IF lead be heated with concentrated sulphuric acid two distinct actions will usually be observed. In the first, bubbles begin to be evolved more or less rapidly from the lead, and in the second, which occurs at a higher temperature than the first, hydrogen and sulphur dioxide are evolved, free sulphur is liberated, and leadsulphate is formed. The second action may be violent and usually continues till the lead is all consumed.Attempts have been made to apply these reactions, by means of a standard procedure, as a "Flash test" for the acid resisting qualities of chemical sheet lead. The purpose of this article is to comment on the best method of performing the test, on the various phenomena which may be observed during the course of it and on the interpretation of the results when obtained.PREVIOUS WORKIn 1919, Barr...

Jan 1, 1930

By M Reid, H Arbon

Hillgrove Resources (HGO) commenced open pit mining in 2011 and from 2011 to 2016 the geology team experienced a consistent negative reconciliation between grade control estimated copper (Cu) grade and the mill received grade. For the first four years, despite trialling various grade control strategies, the monthly variance between geology and mill copper grades fluctuated between -5 per cent to -17 per cent Cu metal depending on the style of mineralisation.In 2015, HGO embarked on various measures which resulted in changes to grade control practices under the advice of consultants. These changes to grade control sampling, estimation and block out practices resulted in six to seven months of consistently poor Mine to Mill reconciliations from -25 per cent to -28 per cent Cu.In an effort to mitigate these poor reconciliations the geology team reintroduced the preconsultant block out and geology driven grade control methods. Blockout reconciliations from this point emulated those seen originally from -8 per cent to -12 per cent (Cu per cent). Early in 2016 the geology team introduced conditional simulation for grade control as opposed to ordinary kriging to better characterise the grade distribution, introduced separate estimation parameters appropriate for every zone of mineralisation, implemented a maximum profit function to optimise the selection of ore and waste, and retained the geology driven block out processes. Since March 2016 the mine has experienced consecutive months of positive Mine to Mill reconciliations, the first seen in six years. Year to date the expected copper metal is within 1 per cent of mill reconciled copper metal.This paper will compare the various sampling methods, estimation algorithms and block out procedures from the past six years to arrive at a robust open pit operating procedure applicable for mineralisation with high short scale variability.CITATION:Reid, M and Arbon, H, 2017. Setting new standards at Kanmantoo – effective grade control procedures, in Proceedings Tenth International Mining Geology Conference 2017, pp 401–408 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

Bendigo Mining operates a 600 000 t/a comminution, gravity, flotation and leaching processing plant for the recovery of gold from their Kangaroo Flat Operation, in the Bendigo goldfields. The free gold and gold bearing sulfi des present are typically coarse grained and hence are highly amenable to gravity recovery. Plant operating data is consistently showing that over 78 per cent of the feed gold is recovered in a circuit, consisting of inline pressure jigs, inline spinners followed by free gold tabling and intensive leaching of tabling tails. The circuit receives coarse crushed product from high pressure grinding rolls and the grinding mill discharge, which allows material to be re-circulated through the gravity process until the particles are small enough to enter the flotation circuit. A plant audit was completed on 26 November 2009 designed to give an indication of the overall operational characteristics of the gravity circuit including single pass efficiencies of associated equipment. The techniques, results and challenges of such a survey are discussed.

Aug 1, 2010

Development of a global failure criterion for rocks has been a desired goal in rock mechanics. Due to variations in factors affecting rock specifications and their mechanical properties, proposing a single failure criterion suitable for all rock types has proven to be unachievable. The theoretical failure criteria do not fit the real data correctly. Amongst empirical criteria, the Bieniawski criterion has demonstrated an acceptable agreement with laboratory generated data. It has been experienced that the ability to estimate rock strength via the modified form of this criterion is significantly improved. Based on the modified Bieniawski criterion and using VB.net, an associated Microsoft Windows program named 'RAMOCE' has been developed. The inputs of RAMOCE can be triaxial compressive strength data, Bieniawski parameters of a specific rock or the type of given rock. Based on input data, potential outputs of the program are Bieniawski's rock parameters, sensitivity analysis of the effective parameters, rock failure prediction and defining the type of given rock.

Nov 25, 2010

By C Hertle, B Goebel, R Fabre

The mining industry maintains a ælove-hateÆ relationship with water. Dewatering, aquifer, water disposal, irrigation, process water, tailings water, run-off water, seepage, leachate and sumps are all terms that are used on a daily basis in the mining industry, highlighting the numerous water usages on site and their associated quality. According to the Australian Bureau of Statistics (2001), each year the mining industry consumes over 530 000 ML of water. The increasing recognition of water as a limited and valuable commodity, and the associated environmental concerns with the management of water disposal to the environment has led the industry into improving on-site water management. Progressively, water balance models and water reuse strategies are being developed, incorporating more sophisticated water treatment processes. By way of example, membrane technologies, once restricted to industries such as the pharmaceutical industry or the drinking water industry, are now entering the mining world with the aim of producing clean water of suitable quality for ore processing or for advanced treatment prior to release to the environment. This paper will provide a review of the threats and opportunities linked to water use and recovery/reuse in the mining industry in Australia. It will open with an overview of current water usage and associated quality for various mineral industries and continue with identifying the threats and limitations associated with the quality of available water. It will then present how newly developed water treatment technologies and assessment tools can be incorporated into the system to enhance the recovery and reuse of water on site, reduce the risks associated with securing long-term water supply and further improve production, environment and safety (health risk control).

Jan 1, 2006

By McQuade CV, Riley SJ

Acid mine drainage is an unavoidable consequence of some coal mining operations. Typically runoff pH is below 3.5 and at these pH levels heavy metals are mobilised. Leachate from coal reject dumps may require collection and treatment to raise the pH and precipitate the metals before being discharged.A bi-product of coal mining operations at Clarence Colliery is coarse washery reject. At present the coarse reject is deposited above ground and rehabilitated. Adjacent to Clarence Colliery is the Kable's Transport Pty Ltd sand mining operation. It has been proposed that co-disposal of the rejects from both operations may produce a product whose leachate has near neutral pH.

Jan 1, 1998

By P G Simpson

The Sundance gold mine, located 2.5 km east of the town of Batchelor in the Northern Territiory, has produced over 5300 oz of gold since it was discovered in 1978. Sundance is unique in the Pine Creek Inlier in that the ore is hosted in palaeo-karst detritus and crystalline magnesite of the Early Proterozoic Coomalie Dolomite. This paper presents a summary of the geology of the mine, and describes the methods used during the two periods of mining.

Jan 1, 1994

By M Hassall, E Humphries

Personal risk assessment processes, also known as Take 5 or SLAM (Stop, Look, Assess, Manage) have been utilised in high hazard industries for over 30 years. However, there is limited research to understand if a personal risk assessment process improves safety and health outcomes. The author’s learnings during discussions with training participants in G3/G-MIRM (Risk Management Systems) and G2 (Risk Assessment for Supervisors) courses have provided them with significant insight into understanding if a personal risk assessment process is valued across a number of mining industry organisations. These discussions arise when the four-layer model is presented (Figure 1) where ‘Layer 4’ represents the last resort risk checking activity. In this context, training participants agree that this process has value. However, the consistent opinion is that the personal risk assessment process is not effective, that it is a ‘tick and flick exercise’ and is not achieving the desired outcomes.

Apr 16, 2024

By A Castleden, G Cavanough, M Kochanek, J Cunningham

ROES« is a proposed new mining system for underground hard rock mines. Ore is accessed from within a shaft, which is located close to or within the stope, and pitched either vertical or within approximately 20 degrees of vertical. The shaft is designed to exclude personnel entry so production drilling and explosive placement is done using remotely controlled or automated machines. Routine remotely controlled survey of the shaft, stope back and broken rock within the stope is typically done following each blast. The survey may include excavation geometry, rock fragmentation and geotechnical characteristics. Blastholes are surveyed before placement of explosives. This provides mine operators and engineers with real-time data, allowing them to monitor production performance and risk factors so that they can make rapid changes as required. ROES« is designed to apply to open stoping or sublevel caving situations either in disseminated, geologically defined, thick tabular or narrow vein orebodies. The technologies developed for ROES« will also have potential applications to block caving operations to reduce the risk of frozen ore and poor fragmentation. In a typical sublevel open stope application, ROES« will reduce the amount of stope-associated development by about half and therefore will allow ore to be brought on-stream sooner and at significantly reduced cost. Other savings are expected to flow from the centralisation of mining activities and operational data, reduction in mining fleet, reduction in ventilation requirements, improved occupational safety and reduced mine complexity. CSIRO and Orica Mining Services are developing the required technology and AMIRA is seeking sponsorship for a project to trial the mining method. This paper details the ROES« method, expected benefits and applications and includes typical stope and mining block designs and design requirements.

Jan 1, 2008

By J E. Powalisz

"The application of automated sampling techniques can help to provide a representative sample of process fluids and slurries that provide data for controlling process, custody transfer and quality assurance and quality control purposes.The automation of sampling provides a more consistent and reliable sampling process and eliminates many of the human-induced errors. Automated sampling can also provide a higher degree of safety in the plant/processing environment as well as better bottom-line results.Automated, fixed volume samplers can provide a very representative sample by integrating many small ‘grabs’ of sample from a process. Automated samplers can be controlled in a variety of ways to optimise the sampling process, including:cycle ratedwell timetotal volume.Properly selected and applied, an automated sampler can effectively isolate the operator from the process fluid during sampling and, to a great degree, during sample container collection.A variety of materials of construction, including seals, are available to handle demanding mining applications. Alloy 625, alloy 2205, AL6XN® and even certain plastics are used successfully in mining slurry applications.This paper explores the application of automated, fixed volume, batch style samplers in copper/nickel and gold processing, specifically pregnant leach solution and extraction fluids.Several specific field applications are discussed, including process installation details, hardware and operation.CITATION:Powalisz, J E, 2014. The application of automated samplers in copper/nickel processing, in Proceedings Sampling 2014, pp 35–42 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 29, 2014

By J King, T Hunter, R Coleman

"The industry that supports operations and new projects is suffering a rapid decline in the currently severely curtailed capital investment environment. This is evidenced by a decline in the number of skilled teams, who are now centred in fewer locations. Other features are an aging and retiring ‘Baby Boomer’ generation, coupled with a low uptake of new graduates and the uncertainty in predicting future capital expenditure programs and requirements. Combine this with a reluctance of cash-poor operations to modernise and adapt in an environment of low metal prices, and there is a real uncertainty in how service providers will meet industry needs as they evolve.The industry that supports operations and new projects is suffering a rapid decline in the currently severely curtailed capital investment environment. This is evidenced by a decline in the number of skilled teams, who are now centred in fewer locations. Other features are an aging and retiring ‘Baby Boomer’ generation, coupled with a low uptake of new graduates and the uncertainty in predicting future capital expenditure programs and requirements. Combine this with a reluctance of cash-poor operations to modernise and adapt in an environment of low metal prices, and there is a real uncertainty in how service providers will meet industry needs as they evolve.Trends amongst service providers will be put forward as well as developing options and alternatives. These embrace a whole gamut of agile alternatives in the areas of partnering, alliances, commercial and shared risk models and mutual innovations. These will be discussed with some case studies and suggested approaches.Particular emphasis will be upon brownfield expansions and upgrades which have emerged recently as a preferred lower capital and focused way to achieve best practical outcome at lowest cost. There are a number of specific features of such brownfields projects including the requirement for very close cooperation between the execution team, operators, maintenance and suppliers and a maximum usage of site resources and ingenuity. Often, required investment hurdle rates are high, downtime allowed is minimal and site resources usage is maximised. This requires mutual trust, good planning and high health, safety, environment and community (HSEC) standards and practice. In many ways the practices and skills needed are the exact opposite of the historical ‘big greenfields’ project with which the industry has been geared for more recently.Another developing area has been with innovative commercial models and practices. These have been as a direct result of the more challenging investment criteria being adopted and the relative hunger of service providers. It has become more common to look at these commercial/costing alternatives very early in the project cycle as an essential project tool and not just as a possible option. These commercial solutions cover such alternatives as leasing and rental, deferred payments, build–own–operate–transfer (BOOT) and build–own–operate (BOO), whole-of-mine preferred spares and maintenance terms, and aggressive performance targets with real assurance penalties. Once again this requires very close mutual dealings and trust, and sufficient time allocation compared to a conventional approach.Citation:Coleman, R, King, J and Hunter, T, 2016. Upgrades, Modernisations and Expansions... Where Will the Expertise, Capability and Skills Come from in the Future?, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 69–76 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

Both blast furnace and steel furnace slags have been used extensively and successfully on main line railroads in the United States for more than 25 years. Annually, these slags are being used as ballast at the rate of about 4 million tonnes of blast furnace slag and 1 mil- lion tonnes of steel furnace slag, much of it on main line with 90 metric tonne car loadings. More steel furnace slag would be used if it was available. Both slags meet all the specification limits of the American Railway Engineering Association. Actual use on high density rail- roads has confirmed the long range economics of their use. Comparison of laboratory tests, such as Los Angeles abrasion, with actual field per- formance has shown conclusively that commonly used laboratory tests can not be used to accu- rately compare the quality of various types of ballast materials.

Jan 1, 1979

Economies in cemented fill demand the utilisation of the full potential of the portland cement component of the mix. If declined tailings are used, it is desirable to establish the optimum particle size distribution. Pozzolic materials and slags are. very useful additions to increase the amount of cementitious material through reaction with calcium hydroxide produced by hydration of the cement. It is also essential to check out the presence of substances which may seriously affect the setting and hardening of the cement or the durability of the cement bond. The importance of quality control in the preparation of cemented fill cannot be over Emphasised.

Jan 1, 1973

By J Wall

The use of electronic detonators in civil tunnelling applications, to reduce vibration in small firings has been successfully utilised for a number of years. As part of the mining industry’s commitment to reducing blast damage during the development cycle in underground mining applications, a series of development blasts using e-Dev™ electronic detonators in a typical mining application was conducted at Resolute’s Mt Wright operations in North Queensland in 2010. Results were based on direct comparisons to the current industry standard of non-electric firings as a baseline, with as many parameters as possible being captured during the trial. Development costs are typically high in most underground mines, especially in capital development headings, which are in waste and therefore of no direct economic value, so by being able to accurately fire to design, costs relating to both ground support requirements and volume of material removed, (and therefore haulage required) can be minimised. A direct comparison of overbreak (ground blasted outside of design) and cast (distance rock thrown from blast) was also made during the trial, as well as close monitoring of the drilling accuracy.

Mar 21, 2011