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By J Rowland

"Ventilation models are invaluable tools for both prediction of routine daily ventilation changesin an operating mine to circuit performance expectations at the mine in 20 yearsÆ time. Arguably ventilation offi cers are becoming increasingly reliant on maintaining an accurate ventilation model with which to do their work. This paper relates to the practical assessment of the accuracy and thus ability of a mine site ventilation model to be reliably utilised on such varied tasks. The author's experience shows that in some cases the incumbent model is found to be in a state of tune that demonstrates a mine wide detailed assessment of branch resistances is simply not required. The money spent on a detailed mine wide ventilation survey that is not required would be far bett er served purchasing much needed monitoring equipment, rather than fixing something that is possibly not even broken. The term ænot rocket scienceÆ has been incorporated into the title of this paper because it appears that many practitioners believe that circuit validation is diffi cult. As long as clear att ention to detail is paid to the actual data collection process then drawing an accuracy comparison between the circuit performance and the model performance at any particular point in time, is really very simple. This paper will show a manner in which a circuit can be analysed to determine its actual state of health by using various diagnostic tools and tips. It will help ensure that subsequent work scopes to address any highlighted model defi ciencies can be more effi ciently scoped and targeted. It will hopefully remind operational people that such self assessments can easily be done æin houseÆ if the appropriate steps are followed."

Jun 1, 2012

By D L. Kennedy

It has always been a challenge to accelerate the underground development progress by increasing the advance rate of each development round. Surveys have shown that most of the development rounds have only been pulled 84 per cent to 94 per cent of the drilled length. Where bare detonators have been used as primers, less advance rate is expected. In order to obtain a good understanding of the influence of priming upon the advance rate in underground development, a series of high energy primer trials has been conducted by Orica Explosives in the goldfields using various types of Orica high energy Anzomex « primers. It has been shown that development face has been pulled an extra 140 mm to 420 mm by priming with Anzomex « K primers compared with conventional primers. From all the trials at different sites, we have seen that the face pulled using K primers was more square than that pulled using conventional primers. Virtually, no butts and toe were left on the face developed using K primers. Computer simulation has been conducted using either a conventional primer, a bare detonator or a K primer as initiator. The study compared the predicted crack patterns developed around the toe of the hole and it was deducted that a detonator-initiated hole would leave a butt some 200 mm longer than that from a conventional primer-initiated hole, and a K primer-initiated blasthole would give rise to stronger initial p-wave, promoting crack development around the toe and increasing the ability to pull close to the full depth.

Jan 1, 1999

By R Forster

Direct ship iron ore (DSO) operations at Extension Hill in Western Australia’s Midwest region have commenced, with fi rst product railed to the port of Geraldton in July 2011. Reserves are 14.8 million tonnes (Mt) of haematite-goethite ore overlying an Archaean BIF-hosted larger magnetite deposit which Mount Gibson Iron Limited (MGI) sold to other parties in 2006.Some unique geological aspects of the deposit shape DSO mining and processing operations. Owner-operator selective mining, blending, crushing and screening on site will produce three million tonnes per year (Mt/a) of Lump and Fines product to be trucked 86 km to Perenjori, railed 232 km to Geraldton, and loaded aboard Panamax-sized ships through the dedicated iron ore shiploader at the Geraldton Port Authority’s Berth 5 facility.The statutory approvals process for this project formally began in 2004, dominating delays in a predevelopment phase which extended over a longer period than the likely life of DSO operations. The lack of transparency, uncertainties and costs inherent in state government processes have influenced decisions made by MGI while assessing other development opportunities in Western Australia. Potential for additional Reserves exists at Extension Hill, however MGI’s ability to extend the mine life will hinge on statutory approval to explore for and evaluate other DSO resources on surrounding granted mining leases.The nature of the resource and use of existing infrastructure for product transport have enabled MGI to keep operating costs and capital intensity of this project relatively low. A tenacious development approach by MGI and robust project economics have fi nally enabled this site to take its place as a revenue earner beside the company’s other DSO operations at Tallering Peak and Koolan Island.

Jul 11, 2011

By S Grant, S Emeric, P Baker, E Jones, D Clark

As we strive for a sustainable and resilient future, repurposing assets has become a top priority. In Australia alone, we have a significant number of mineral projects in the pipeline, extensive existing operations, and over 50 000 legacy sites. Collectively, this presents a unique opportunity to be a world leader in mine rehabilitation. Complex stakeholder landscapes, inflexible policies, aged regulatory frameworks, technical uncertainties and increasing liabilities are all barriers hindering effective transition of legacy assets. The impetus for change is further catalysed by shifting consumer preferences, workforces in flux and regional Australians questioning what the transition means for their local community. We need innovative approaches to take a leading role in the industry and support global efforts more broadly. Co-designing an ambitious, shared vision spanning projects, operations and legacy assets with all key parties is a fundamental step to unlock and realise maximum societal, environmental, economic and reputational value. Serious play and gamification can further enhance this visioning process.

Aug 2, 2023

By M K. C Roberts, M G. Magwaza, J W. L Hanekom, P Piper, R Lousteau

Due to the perceived potential to extract the second economic manganese seam at its Black Rock Operations in the Northern Cape Province, South Africa, Assmang commissioned an investigation with respect to mining method and sequencing of the two orebodies in 2007. Based on this initial study into multiseam potential, conditions and impacts, the rock engineering aspect was expanded to determine conceptual rules to govern the extraction of both manganese seams using the normal bord-and-pillar layout implemented at this operation. This work included the theoretical analysis using basic pillar design practices and numerical modelling, including the use of Map3D, UDEC and Phase2 codes.In 2013, Assmang launched a large-scale investigation into the potential to increase mine output from all possible manganese sources at the operation. Included in this investigation was the requirement to confirm or modify the conceptual multiseam extraction rules to implementation. As part of this confirmation process, stress measurements, borehole camera audits and additional numerical modelling were performed at a particular site on the operation where a limited extraction of both seams had been undertaken. The results obtained from this process provided confidence in the conceptual extraction rules and allowed the derivation of final extraction rules that will be implemented at the operation as the multiseam mining process becomes more widespread.CITATION:Hanekom, J W L, Roberts, M K C, Magwaza, M G, Lousteau, R and Piper, P, 2014. Confirmation of multiseam extraction rules for Black Rock Manganese Operations, Assmang, Northern Cape, South Africa, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 107–116 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By H He, S Tillotson, S Gibbons, J Shaw

"Water evaluation and management during mining exploration and operational activities is crucial to minimise direct and indirect operational costs and also in delivering mining companies the less tangible, but equally critical æsocial license to operateÆ.Mining is often carried out in remote areas, where the mine will be the most significant and visible user and potential contaminator of water resources. However, wherever it is located, a mineÆs use of water must be managed in the context of two key aspects: the natural parameters of the resource; its abundance, its temporal variability and its chemical and physical qualities other users of the resource; other industry, potable water supplies and ecological requirements of local habitats.It is vital, therefore, that this commodity be assessed to an appropriate degree to help establish the viability and sustainability of the mining project and identify those other stakeholders who may be affected by the mining companyÆs activities.This paper outlines the background to catchment-scale model and presents a cost-effective method for establishing a robust water baseline and creating a water management tool to be used throughout whole mine life cycle. Numerical surface and groundwater modelling has long been established as a tool for reactive management, following collation of yearsÆ worth of data. Now, using freely available remote sensing data and desk study information, analytical modelling techniques can be used cost effectively to provide mining companies with a tool for assessing and managing their water consumption requirements at the outset of a new project venture.The paper includes a selection of case studies to show how the use of analytical modelling can be used as an evaluation and management tool to help not only assess general watershed parameters and water availability but also how it can be used as a tool to provide decision makers with the information to complete æwhat if?Æ scenario assessments. The case studies illustrate how a combined hydrological and hydrogeological model may enable identification of sensitive receptors, water competition issues and contaminant migration pathways to help manage the risks associated with water consumption and its potential contamination from exploration and operational activities.CITATION:Gibbons, S, Shaw, J, Tillotson, S and He, H, 2013. Catchment-scale water modelling and its role in risk management during mining exploration, in Proceedings Water in Mining 2013, pp 175-188 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 26, 2013

By J Gotte, C Morley, J Froud

Newcrest Mining LimitedÆs Telfer Mine is a world-class gold and copper producer, situated in the Great Sandy Desert, in the north west of Western Australia. The mine has a number of distinctive characteristics such as being one of AustraliaÆs most remote mine sites, being within 270 km of the hottest town in the southern hemisphere (Marble Bar) and having been shut down and reopened after a two-year feasibility study. The construction of a new plant and reopening of the mine gave Newcrest the opportunity to review their mining practices and systems including the opportunity to incorporate reconciliation as a core process. Telfer is now well on the way to being one of the largest gold and copper concentrate producers in Australia. When the mine reopened in June 2003, Telfer implemented SnowdenÆs Reconcilor software system to facilitate reconciliation of geological models, production data and plant measurements. The system was implemented on site in June 2004, as a web-based information management system, integrating other existing mining and plant software packages. It continues to provide an auditable process and consistency of data, providing ease of analysis with standard and customised reporting. This paper provides a case study of the reconciliation system implementation at Telfer. It outlines the consolidation of a number of management systems into one centralised system that can be used to compare and reconcile the tonnes and grades from the mine through to the mill. The authors outline the key estimates and measures that are used for reconciliation at Telfer, detailing the characteristics of the system used to capture the information and the benefits that have been gained through the use of a rigorous reconciliation process on a complex orebody.

Jan 1, 2007

By T Warren, A Dempster, N Barnett, J Oh, S Saydam

The influence of the insulating properties of lunar regolith was shown in the sub-surface temperature tests performed by the Apollo missions, with no significant temperature fluctuations occurring below 80 cm from the lunar surface even if surface temperatures fluctuated >200 K between lunar days and nights (Heiken et al, 1991). Key to the thermal insulation of the regolith is its low density near the surface having the greatest insulative effect with the lunar regolith becomes denser with depth. As the regolith becomes denser, the thermal conductivity of the regolith increases (Hayne et al, 2017). Thermal modelling software, Oxford 3D Thermal Model, which mapped the lunar surface temperatures effect on the thermal influence at the lunar south pole sub-surface over a lunar year found areas with brief illumination with surface temperatures >120 K could have sub-surface temperatures <112 K that can sustain long-term stable water ice at depths of <30 cm (Paige et al, 1992; King et al, 2020). Further to this, the observation of water molecules or other hydroxyls by the NASA/DLR Stratospheric Observatory for Infrared Astronomy (SOFIA) in non-permanently shadowed regions (PSRs) on the Moon, indicated that water could be present beyond PSRs (Honniball et al, 2021). Using the Oxford 3D Thermal Model in selected regions in the lunar south pole, can provide insights into the location and depth of cold traps that could sustain water ice.

Nov 29, 2022

By J Visser

Dust mitigation has long been seen as nothing more than managing a nuisance issue, but the reality is that poor dust management can lead to one or more of the following negative consequences: an increased risk of safety incidents, lost revenue, reduced and possibly even lost licence to operate, regulatory intervention, high staff turnover and/or absenteeism and occupational health and safety (OH&amp;S) issues. Dust mitigation and management is not a black art; rather it is a scientifically driven process that can provide an opportunity to increase profits, increase the companyÆs status as an excellent corporate citizen, enhance staff retention and reduce the safety risk profile of the operation.The way to achieve success in dust mitigation and control is to apply the scientific method to each problem that can arise and plague any operation by using current industry best practice. This method of dust problem-solving can be applied to dust issues arising from specific dust sources and locations. The dust sources can include wind impacting on stockpiles, open areas, tailings storage facilities, moving train and truck loads, vehicular traffic on roads, the operation of shovels, front end loaders, draglines and other equipment, as well as ore movement on conveyors.The solutions will come from a combination of deployment of dust collection equipment, dust and moisture monitoring equipment, the appropriate application of water and chemicals, the introduction and maintenance of appropriate barriers and the use of predictive data from local and public weather stations. The paradigm shift required is to view dust mitigation as one aspect of normal operational practice, not a ænice to haveÆ or æunnecessary expenseÆ as most operators currently view it. This attitude is becoming more important as more and more local communities oppose the development of mines. One of the reasons for this local opposition is the inevitable dusty environment that is usually associated with mining.Dust mitigation is not a significant expense if correctly designed and included into the system, either as part of the original design of the operation or as a brownfield installation after the fact. Indeed, there is always a loss of revenue associated with dustiness resulting from ore movement and avoiding this goes a long way to paying for any associated dust mitigating costs.CITATION:Visser, J, 2013. Dust mitigation - changing the paradigm, in Proceedings Iron Ore 2013 , pp 27-38 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By A Bax, G Wardell-Johnson, W P. Staunton, J McGrath, J J. Eksteen

Since 2001, the AMIRA P420 gold processing technology project series has been studying the recovery of gold using gravity devices, with particular emphasis on the centrifugal units, Knelson and Falcon concentrators. The work has entailed the surveying of operating gravity circuits in Australia, Africa and North and South America.This paper reviews some of the results and lessons of these studies, including common circuit operating and design factors, which limit gravity recovery; pointers towards effective modelling of gravity circuits; and the contribution of gravity to overall gold recovery.CITATION:Wardell-Johnson, G, Bax, A, Staunton, W P, McGrath, J and Eksteen, J J, 2013. A decade of gravity gold recovery, in Proceedings World Gold 2013 , pp 225-232 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By M Yahyaei, F Vos, J Siliezar

Site-based case studies (including data collected from industrial surveys) and their application in evaluating circuit performance, have a significant role in developing reliable process models. Such models are useful to both plant metallurgists and researchers. Appropriate process models enable the plant metallurgist to assess the impact of different operational parameters on the overall circuit performance. They also provide the researcher with a detailed understanding of process behaviour in response to changes in ore characteristics and process conditions (ie plant throughput, ore competence, ore type). Thus enabling the identification of effective operating factors, and allowing them to be ranked in order of their influence on the process response, which eventually develops into a process control tool in the hands of plant operators.The above approach has been developed and applied at the Julius Kruttschnitt Mineral Research Centre (JKMRC) separately for both comminution and flotation processes. In recent years, the JKMRC has attempted an integrated approach by developing process models that incorporate the impact of upstream processes on downstream processes. This is not possible using the traditional approach of separate comminution and flotation surveys, so conducting integrated plant surveys is crucial for success in developing integrated process models. This paper summarises industrial experience gained while conducting such an integrated plant survey at Glencore’s Ernest Henry Mining operation near Cloncurry in north Queensland. An appropriate approach should be taken to enable the alignment of different requirements from different processes during the plant survey. This, as well as the challenges faced in integrating comminution process models with flotation process models, are identified.CITATION:Yahyaei, M, Vos, F, Powell, M S, Siliezar, J and Perkins, T, 2014. Challenges in developing integrated process models based on industrial survey data, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 437–446 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By A Hughes, J Agius, T Ferguson, A Parbhakar-Fox, D Lester, L M. Jackson

Management of historic tailings is a major challenge facing the mining industry and its regulators. However, through improved mineralogical and chemical characterisation of such materials the opportunity to develop better rehabilitation strategies arises. Microanalytical techniques including microscopy, mineral liberation analysis and laser ablation inductively coupled plasma mass spectrometry (ICPMS) allow for improved tailings characterisation – but the challenge posed by these techniques is how to use them effectively. Additionally, data sets collected by such techniques must be properly integrated, only then can they assist in the identification of the most appropriate rehabilitation strategies. A study conducted at the Old Tailings Dam (OTD) located at the Savage River Mine, Tasmania allowed for the integrated use of several microanalytical techniques to help evaluate the benefits of a shallow water cover as a potential rehabilitation strategy. Samples (n = 144) from 14 trenches and 11 boring cores (2 m maximum depth) were collected across the OTD. These were subjected to routine acid-base accounting, with a subset subjected to detailed mineralogy using a modified sulfide alteration index (SAI), X-ray diffractometry and mineral liberation analysis (MLA). In addition, representative samples (n = 6) from across the OTD were subjected to laser-ablation ICPMS to characterise the pyrite chemistry. Our results showed that tailings in the northern area submerged under a natural water cover were relatively unoxidised from approximately 1 m depth, with SAI values of 1 to 2. Tailings from the subaerial southern portion were extensively oxidised to approximately 35 cm depth (SAI = maximum 5.8), with fresher materials observed underneath (SAI = 5 to 5.8). Pyrite from across the OTD is enriched in Co, Cu and Ni. Through the integrated application of microanalytical tools, we determined that establishing a water cover of at least 1.5 m depth across the OTD is a suitable rehabilitation option for this historic site. However, consideration for the reprocessing of these tailings to extract Co should be further investigated.CITATION:Jackson, L M, Parbhakar-Fox, A, Hughes, A, Agius, J, Ferguson, T and Lester, D, 2015. Microanalytical evaluations of the savage river old tailings dam, north-?west Tasmania, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 111–124 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

During a mineral exploration programme in an environmentally sensitive area near Mount Painter in South Australia, a helicopter was used to position, construct and service drilling rigs in order to avoid the need to create new access tracks. The drilling programme was designed to optimise the advantages of natural landforms in order to minimise the environmental impact of site construction and drilling activities. This minimisation of land disturbance reduced the required amount of rehabilitation measures to the extent where all impacts of the helicopter-supported programme had disappeared within twelve months of completion of work.

Jan 1, 1995

The Golden Cross mine is situated in a sensitive environmental setting on the North Island of New Zealand, about 150 kilometres south-east of Auckland and about 8 kilometres NW of Waihi. The mine is situated in dipping topography, with volcanic ashes making up soils, fault zones running through the area, and rainfall of about 3m per year on average. Water management is the most demanding environmental challenge on site, and a comprehensive programme has been put in place to address tailings deposition, long term tailings storage, and water treatment during and after operations.

Jan 1, 1995

In recent years rehabilitation of mine sites has become a principal focus of mining legislation in Victoria. In previous eras, managed rehabilitation commenced, if at all, towards the end of mining operations. Planning for rehabilitation works now commences before an exploration licence is granted.The paper gives a brief overview of the requirements for rehabilitation under the Mineral Resources Development Act 1990, Extractive Industries Act 1966, and related environmental planning legislation including rehabilitation bonds and enforcement provisions.A brief review of the current taxation provisions is also included.

Jan 1, 1992

The Elgas Underground Storage Facility at Port Botany, Sydney, is the first purpose-built cavern of its kind in Australia and provides large capacity, safe and environmentally benign storage of Liquefied Petroleum Gas (LPG). The facility will provide Elgas with the flexibility to source product at competitive prices and ensure long-term security of supply. Construction has provided Orica Australia, formerly ICI Explosives, with a unique opportunity to provide a bulk explosive delivery system specifically designed to meet the exacting demands of the site and of the project.

Jan 1, 1999

Alcoa of Australia Limited owns and operates a 150 MW power station adjacent to the coastal township of Anglesea in south western Victoria.The power station was constructed in the mid 1960s to supply electricity to the Company&apos;s smelter at Point Henry, near Geelong, and is fuelled by high quality brown coal mined at the site in Alcoa&apos;s lease area.The open cut mine, producing approximately one million tonnes of coal per year, utilises a backfilling method and has carried out progressive regeneration of those completed areas since the mid 1970s.

Jan 1, 1992

Cordeaux Colliery is more logically sited than the historic escarpment Corrimal Colliery, on the same reserve. At Cordeaux the modernisation of mine plans and equipment and the introduction of high production longwalls have created a record achieving producer of both steelmaking and export coals.Further changes achieved have been in employee related attitudes and performance, enhanced by business strategies and total quality control and particularly benefiting from innovative employee input With this present example of co-operative effort Cordeaux Colliery will continue to improve through management of total quality. resources, development rates and customer satisfaction.

Jan 1, 1991

By Scott RM

The project management and construction plans adopted by Davy McKee for the Cooper Basin Liquids Project resulted in a project notable for the Relatively short duration from initiation of the design through to liquids production. Two locations were involved, one at Moomba in the far northeast of South Australia some 800 km from Adelaide, and the other at Port Bonython some 40 km from Whyalla. Total expenditure by the owners at the two sites was in excess of $600 million. Matters covered include organisation, transport, construction, industrial relations, project services and commissioning.

Jan 1, 1986

During the development of Lorca tunnel project in the South-East of Spain, an in-site study has been done, with the purpose of obtaining the characteristics of the different lithological units through twenty-two parameters for the design of the tunnel excavation and support. In the paper both the different works developed and the different methods and criteria followed in the obtention of the parameters are described. The values of those parameters may be useful in similar cases. Also a summary-table of the parametrical characterization for the use in similar studies is given.

Jan 1, 1987