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By M Jones

The past 100 years the mining industry can be characterised by a focus on increasing financial returns often to the detriment of social, human, manufactured and environmental capitals. Despite the sustainable development principles promoted by the International Council on Mining and Metals (ICMM), the Equator Principles and the African Mining Vision, which should have enhanced project promoters’ ‘licence to operate’ within a host community or nation, the industry has often failed to integrate proven innovations and best practices that enhance sustainability outcomes for mineral resource projects. This failure has led to delays, the abandonment of projects, with value destroyed for promoters, governments, host community and investors.The paper will outline the application of proven innovations, Enterprise Optimisation (EO), and Sustainable Operations (SUSOP®), during the pre-feasibility phase of a project. By determining the value of each capital before and after the application of proven innovations, the presentation will outline how and where value can be created across all five capitals over the life of a project or operation.The paper will demonstrate how the application of proven innovations significantly transforms the value-proposition of a mineral resource project or operation by generating additional value across all of the five capitals, reducing project risk, thus generating value for all stakeholders.CITATION:Jones, M, 2015. Fundamentally transforming the economic and sustainability signature of mining assets, in Proceedings Third International Future Mining Conference, pp 169–180 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By C Hawtin, B Miller, D Ashton

Ernest Henry mine (EHM) is an Iron oxide copper-gold sublevel cave mine located 30 minutes north of Cloncurry in North-West Queensland. The underground mine lies beneath open pit excavations, which were in operation from 1999 to 2011. Fault structures carry large quantities of water from the cover sequence aquifer into the underground mine area. The open cut excavations exacerbates vulnerability of the underground mine to the high intensity wet season storms of northern Queensland. These factors combine to make hydrogeological issues high priority for mine operation. Water-related risks include the cost of removing water from the mine, flooding risk and mud rush potential.Turnover of key technical staff in late 2015 at EHM resulted in the mine being left in an untenable position of losing the primary source of technical knowledge. Due to encouragement of cross-disciplinary activity coupled with workload and resource sharing, the management team were confident in utilising on-site personnel to offset loss of experienced personnel.Remaining geology personnel took additional responsibility for hydrogeological monitoring equipment and planning of upcoming work. Consultant input was limited to review only and an emphasis was placed on knowledge transfer to the geology team. Using this strategy, a 13 hole dewatering program was successfully implemented, achieving a significant water level drop in areas of elevated hydrological risk, whilst also upgrading the hydrological monitoring sensor array.Through a development program centred on cross-disciplinary exposure, the technical team was able to retain key technical knowledge despite staff turnover and produce strong results outside traditional training and roles. This paper serves as a case study on the methods, strengths and drawbacks of putting a focus on cross-disciplinary exposure as a method to combat staff turnover.CITATION:Ashton, D, Miller, B and Hawtin, C, 2017. Go with the flow – managing hydrogeological staff turnover at Ernest Henry mine, in Proceedings Tenth International Mining Geology Conference 2017, pp 129–136 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By P J. Willems, B J. Junor

Blackwater Mine is in the central-southern Bowen Basin, immediately south of the township of Blackwater on the Capricorn Highway. The current open cut operation extracts coal from three main seams, designated Top, Middle and Lower, in the Late Permian Rangal Coal Measures cropping out on the eastern flank of the Comet Ridge. Complex geological structures, dominated by E-W normal faults and N-S reverse faults, have significant detrimental effects on coal mining operations. Historical exploration before 2010 involved several types of drilling only to understand structure, coal quality and washability. Hence, although drilling data was combined with limited pit mapping and observation, unknown structures were still often encountered during excavations and led to mining surprises. In 2010 BHP completed 200-line km of closely spaced 2D seismic survey to capture gross and detailed structures followed by fit for purpose structural drilling to confirm major structures in the northern part of the mine. In 2018 a high density 9.2 km2 3D seismic survey was completed in the southern part of the mine. Subsequently, a 17.2 km2 survey was completed in 2020 to cover the northern active mining area. It allowed geoscientists to successfully map previously unknown major faults and seam splits, which could potentially impact the mineability of the area. It is important to note, that faults interpreted using modern high-density 3D data can be interpreted with dramatically higher confidence in the fault dip and azimuth orientation in comparison to the legacy 2D data. Along with targeted drilling, pit mapping and structural interpretation, the outcome adds value to mine planning and operations. This paper outlines recent successful seismic 3D data acquisition and interpretation. In detail, the paper presents case studies on how the data can be incorporated into a structural model to improve geological knowledge, enable geotechnical assessment, and support safe and efficient coal mining in a large and structurally complex mine.

Mar 22, 2022

By J R. Robinson

Prior to mine development, exploration drilling within the Luise Caldera on Niolam Island encountered gold mineralisation to the northwest of the main Minifie and Lienetz orebodies. This mineralisation was referred to as the Kapit orebody, and ten diamond drill holes were subsequently completed over the area to investigate its economic potential. Several significant mineralised intercepts were returned. These were interpreted using the orebody model developed for Lihir at that time which invoked a strong horizontal control to mineralisation. Additional consideration was given to the elevated geothermal temperatures encountered, the proximity of the mineralisation to the ocean, and its perceived depth below sea level, resulting in the Kapit area being given a low priority for follow up investigation. As a result, no further work was completed over Kapit until recently. The Kapit orebody was the target of an intense diamond drilling programme during 2002/2003. Data from this latest round of drilling has significantly improved understanding of the mineralisation and associated geology. The significant orebody now delineated at Kapit substantially differs from past interpretations, and the latest data has upgraded its economic potential. A resource estimate and other critical studies completed in 2003 enabled an updated reserve statement to be issued in February 2004 including the Kapit mineralisation for the first time. Total Probable Reserves at Kapit stand at 25.2 million tonnes (Mt) at 5.28 grams of gold per tonne (g Au/t), for a total of 4.3 million ounces (Moz) of contained gold.

Jan 1, 2004

By Waterhouse J. D, Harris B. M

This paper briefly describes the construction in 1979/80 of a 70m deep trial open pit coal mine near Bowmans S.A. and describes more fully the hydrogeological aspects of the exercise. The primary purpose of the Trial Pit was to provide a large sample (700 tonnes) of coal for combustion tests to be carried out in West Germany and the United States of America. Consideration was given to obtaining the sample of coal by drilling and by shaft sinking as alternatives to open pit methods. It was expected that economic mining of the deposit on an operational scale could only be achieved by open cut methods and it was recognised that major uncertainties existed in planning such a mine in the deep unconsolidated multi-aquifer deposit. It was therefore elected to obtain the bulk sample by constructing a trial open pit, which would be closely monitored to provide as much data as possible for future planning of a full scale mine. The dewatering of the Trial Pit was achieved using 26 deep pumping wells, assisted in the later stages by several hundred well points. This was probably the largest dewatering project currently in operation in Australia.

Jan 1, 1981

TSL Concepts and Practical Examples of the Non-Reactive System - Meyco TSL 865 Thin Spray-on Liners (TSLs) have been intensively investigated by mining and chemical industries within the last decade. Apart from the basic concept of spraying thin liners, expectations of the product's performance vary, eg immediate active strata support is seen as a key to control the ground permanently. For many coal mines this is an important factor to reduce maintenance in their roadways and enable permanent production from the long wall. In opposition to a passive mesh system this technology offers immediate active support to the strata. But not only coal mines are interested in TSL technology, there are potential applications in hard rock mines, during shaft sinking, pillar support and as an anti-weathering sealant. This paper will explain the advantages and disadvantages of TSL concepts; it will give examples of successfully applied TSLs with a main focus on the non-reactive and flexible system MEYCO TSL 865 by BASF. Furthermore, it will indicate the limitations and discuss briefly the bearing capacity and reasonable lab testing of such systems.

Nov 25, 2010

By S S. Kanchibotla, E J. Sellers, L Julian, A Musunuri

Fume events in coalmines are typically associated with wet conditions, soft ground and deep holes. An ACARP research project used laboratory and field testing combined with literature reviews, numerical models and field investigations to characterise the influence of these conditions on the propensity for fume. This paper highlights the results for soft ground and wet conditions and proposes a proactive fume mitigation methodology. A simple numerical model is used to show how fume arises in soft rock that yields more under the loading of high-pressure, water-resistant explosive blends than for ANFO. The blends cool more rapidly after detonation into the lower temperature zone favourable for NO2 production. Low-pressure, high detonation temperature explosives are loaded or charged into soft ground. Water resistance must be considered because soft, faulted and fractured ground can lead to fume from degradation by water flow and non-ideal detonation of product in cracks.A suite of tests were developed to quantify ANFO and emulsion blend performance over time that can be carried out in a mobile laboratory on-site. Index tests such as viscosity measurement and water resistance in beakers are proposed to quantify long-term product performance because small components, such as surfactant, prill impurities and prill fines, contribute to inconsistent product performance. Water ingress experiments and detonation tests aligned with field investigations identified and characterised the role of groundwater in damaging ANFO and causing fume.Fume risk management is achieved using a proposed proactive fume mitigation methodology to characterise influences such as seasonal rain variation, groundwater flow hydrogeology, rock mass strength and structure well ahead of blast design. The design of blasts and selection of explosive products to consider expected conditions will reduce fume, improve efficiency in the mine and offer cost advantages.CITATION:Julian, L, Musunuri, A, Sellers, E J and Kanchibotla, S S, 2015. Mitigation of post-blast fume in soft ground and wet conditions, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 511–518 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By M W. N Buxton, M T. Bootsma, J Benndorf, C Alford

Research in the field of cut-off grade optimisation has shown a relationship between cut-off grade, project life and net present value (NPV). Lane’s theory demonstrates that cut-off grades can be optimised in order to maximise project profitability. Although the theory forms the basis for many open pit mining projects, application of the theory in underground mining remains limited to-date. The main reason for this is the complex interaction between all processes in underground mine planning, which makes it difficult to apply Lane’s mathematical optimisation approach.Recently a new stope optimiser product was released. The AMS Stope Optimiser automates the design of underground stopes at user-defined cut-off grades and allows for rapid evaluation of mine designs at different cut-off grades. Using this software, an optimisation approach was developed and validated on an underground gold deposit in northern Sweden. Potential project NPV increased by approximately 30 per cent when using this new approach.Spatial grade uncertainty in mineral resources was identified to be a major risk in underground stope design. The optimisation approach was further extended to account for grade risk using estimated and stochastic simulated resource models. The resulting optimisation process accounts for grade risk early in the design process and reduces the risk of a stope not meeting the cut-off grade with subsequent financial loss.CITATION:Bootsma, M T, Alford, C, Benndorf, J and Buxton, M W N, 2014. Cut-off grade-based sublevel stope mine optimisation – introduction and evaluation of an optimisation approach and method for grade risk quantification, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 281–290 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

Alluvial mining even of shallow deposits is often economically a marginal proposition and causes significant disruption of the land surface through the need for large scale excavation. In-situ leaching using chlorine-based solutions eliminates the need for excavation, the disruption of surface activities, and may greatly reduce processing costs and improve recovery especially of fine gold. A spreadsheet model has been developed to design and analyse the economics of in-situ leaching of alluvial deposits. In-situ leaching of shallow deposits may be achieved in a number of ways including solution infiltration via perimeter ditches or the use of injection and production wells. In most instances deeper alluvials may only be processed using well systems. Two deposits are analysed in this paper. The first consists of one metre of payable wash beneath one metre of overburden. Some thirty fields per year are treated processing 450 000 BCM per year at a cut-off grade of around $4/tonne ($8/rn3 or the gold value equivalent of 0.26 gh or 0.52 g/m3). The principal costs are well drilling and labour. Sensitivity analysis indicates that doubling the throughput halves the cost. The economics of the project are relatively insensitive to reagent costs and consumptions, and halving the recovery doubles the cut-off grade. Shallow deposits treated using the infiltration ditch system may be marginally cheaper and more conveniently managed although this depends on the relative cost of digging the perimeter ditches. In a second example, deep leads with one metre of wash beneath 30 metres of overburden necessitate significant drilling and feature reduced throughputs as a consequence. In the example chosen 30 fields a year are processed for an annual throughput of 65 000 tonnes costed at around $20/tonne (1.4 g/t Au equivalent, $40 /m3). Sensitivity analysis indicates that throughput, and drilling cost per metre are not important but there is a high sensitivity to recovery and to the depth to payable wash.

Jan 1, 1992

By E de Necker, F D. I Hodg, L-M Cruywagen

The acid mine drainage (AMD) situation at three opencast collieries in the Witbank Coalfield, South Africa, was evaluated from different perspectives. Twenty-seven test pits were dug into the spoils of these collieries to characterise the in situ conditions of spoils of varying age. Detailed static testing was done on surrounding drill holes and additional samples were taken from the test pits. Selected samples were tested using different techniques, namely ABA, mineralogy and kinetic tests. Groundwater monitoring boreholes from the areas surrounding these spoils were also used for characterisation. The ABA results compared favourably with the in situ determinations; acidic test pits proved to be potentially acid-generating from ABA, even when the samples had neutral paste pH. Kinetic test results showed these samples to yield low pH leachate over the test period. In several of these results, the theoretical depletion of neutralising potential and the onset of acidity were well matched. NAG pH-values and final observed water chemistry corresponded for the cells predicted by ABA to acidify, but compared poorly in cells that did not acidify. Results from the non-acidic spoils were consistent with the in situ observations. Alternative kinetic test methodologies were also employed. Duplicate samples were tested in humidity cells and in aerated trays that were manually wetted on a regular basis. Results from these tests showed an excellent correlation. Detailed mineralogical determinations using XRD and XRF were used for comparison to the ABA and, in some cases, humidity cell results. These comparisons show that the ABA results are consistent with the results expected from the mineralogy. The conclusion from these assessments is that ABA, in most cases, provides information that can be correlated to the field, mineralogy and to humidity cells. The use of multiple techniques leads to a higher degree of confidence in the use of the data.

Jan 1, 2003

Waihi Gold Mining Company Limited, a wholly owned subsidiary of Normandy Mining Limited, operates the Martha gold mine, located in the township of Waihi, New Zealand. The operation, an unincorporated joint venture, comprises Normandy Mining Limited (67.070/0) and Otter Gold Mines (32.94%). Since gold was first discovered at Waihi in 1878, it has formed a key part of the region's economy. In 1909 the Waihi mine was described in a report to Parliament as æthe most important gold mine in Australasia and one of the greatest in the world.Æ That was a record year for production, with 416,813 tons of ore mined and some 1,120 men employed. Today the mine produces up to 1,250,000 tonnes of ore annually, and the project employs some 234 men and women. In 1999 the value of the gold and silver produced ($59 million) made up 47% of Waihi's estimated GDP. Waihi Gold has made significant contributions to the Waihi economy, community and the Hauraki region as a whole. Since the mine was re-opened in 1987, thousands of local people have benefited from the mine. In 1999, consents were granted allowing an extension to the mine life (the Extended Project) and this will result in a further seven years of economic benefits resulting from mining activity. The Company has undertaken extensive consultation throughout project planning, construction, operations and rehabilitation. Ongoing liaison and involvement with all community sectors, including Tangata Whenua and Iwi, local residents, recreational groups and schools remains an integral part of the operation. Throughout the life of the modern Martha Mine, the Company has actively supported the local community in the form of donations, sponsorships, the provision of amenities, and by participating in community events. A well established environmental team exists at the site. Environmental and community performance is measured by an independent five-assessment process, and the Company is committed to achieving excellence through ongoing improvement programmes and staff awareness. When the mine is closed, the open pit area will be transformed into a recreational lake, and the tailings storage facilities will be rehabilitated to become a combination of wetlands, grassed areas and ponds. Resources will be provided by the Mine to ensure the rehabilitated site remains in a safe and self-sustaining, stable condition in perpetuity. The mine is regarded as a showcase on a world standard of how a modem mining operation can successfully coexist with the nearby community.

Jan 1, 2000

By A Guillen, J-P ChilFs

Most 3D geological modelling tools were designed for the needs of the oil industry or detailed mine planning and are not suited to the variety of situations encountered in other application domains. Moreover, the usual modelling tools are not able to quantify the uncertainty of the geometric models generated. The potential field method was designed to build 3D geological models from data available in geology and mineral exploration, namely the geological map and a digital terrain model (DTM), structural data, borehole data and interpretations of the geologist. This method considers a geological interface as a particular isosurface of a scalar field defined in the 3D space, called a potential field. The interpolation of that field, based on cokriging, provides surfaces that honour all the data. The 3D model and its parts are always consistent with the observations. New developments allow the covariance of the potential field to be identified from the structural data. This makes it possible to associate sensible cokriging standard deviations to the potential field estimates and to express the uncertainty of the geometric model. It also, for the first time, gives a statistically optimal, geologically sound way of interpolating geology, other than directly joining the dots as you do with CAD. Practical implementation issues for producing 3D geological models are presented: how to handle faults, how to honour borehole ends, how to take relationships between several interfaces into account, how to model thin beds over many kilometres, how to optimise lithological properties and how to integrate gravimetric and magnetic data. We describe all geology surfaces and volumes using implicit functions. These are then rendered onto the required sections, plans, etc. The estimation of orebody grades and tonnes, using an unbiased and optimal geostatistical technique, makes use of the stratigraphically bound 3D geology model. An application to the geological modelling of the Hamersley iron ore district, Australia, is briefly presented.

Jan 1, 2009

By S Novak

A world-class example of sustainable development in practice, the Local Resource Development Initiative (LRDI) grew from agreements between the Ambatovy nickel mine developers and the Government of Madagascar. A program of training and community development, the LRDI aims to maximise local benefits by optimising the integration of local resources during the construction period of the mine. By local resources, we mean the local labour force as well as local goods and services. Begun in 2007, the foundation of the LRDI is to integrate local resources into the mining project and where gaps are identified, design and implement training, mentoring and other programs to fill those gaps. The principal accomplishments are: the establishment of training centres that trained over 4000 people in little over one year, 96 per cent of whom hired to work at the mine; a support program for local micro, small and medium enterprises that has led to the award of 65 contracts for goods and services with training and mentoring of over 100 local businesses; and a number of special projects that have, among other results, strengthened local agricultural development and created employment for young people. The LRDI provides unique insights into key indicators and lessons learned to strengthen the social and economic sustainability of mining projects in developing countries. The paper will discuss these in terms, among others, of: the importance to project success of upstream planning to address socio-economic issues; the role of civil society and other local partners to strengthen and expand sustainability outcomes, and to spur governments to demand that major projects promote economic and social sustainability; and the integration of mine sustainability with sustained regional social and economic development.

Jan 1, 2009

By P A. Jenkins, I W. O Jones

WMC has mined the Perseverance disseminated orebody exclusively by SLC (sublevel cave) methods. Deteriorating ground conditions in the vicinity of an orebody inflection forced a re-evaluation of future mining at Perseverance and a strategy to drop down below the inflection zone and recommence the cave was implemented. This strategy has led to increased production at higher grades, resulting in lower costs and better mill recoveries. This paper describes the evolution of mine planning, development, support and production strategies through the successful process of implementing the ædrop-downÆ and re-establishing the SLC.

Jan 1, 2000

By B Y. Luan, Y Tian, W Zhou, X Lu, Q X. Cai

The unmanned driving technology in open pit coalmines is an important technology that relies on innovation to drive the development of the open pit coal mining industry in China’s transformation of growth drivers and industrial structure upgrading. It is an important path to solve the shortage of mine truck drivers in the future mining, an important way to improve the working environment of open pit mining personnel, and an important foundation for achieving flexible production capacity in open pit mining to cooperate with the coordinated development of new energy. The communication rules at intersections are key to ensuring the safety and efficiency of unmanned driving in open pit coalmines. This paper proposes a collaborative traffic strategy between unmanned trucks for the single bucket unmanned truck intermittent process system in open pit coalmines. Based on the gap theory, this paper analyses the conflict characteristics and establishes a coordinated traffic strategy for the common intersection and merging conflicts of unmanned truck trucks in open pit coalmines, A multi-agent system simulation platform was built to evaluate the coordinated traffic efficiency under different initial average gap sizes of vehicles, with intersection traffic density, vehicle speed, and gap changes as key indicators. The results show that under the simulation conditions of this article, when the initial average gap of vehicles reaches three (four) times or more of the safe distance, the coordinated traffic performance of intersection conflicts (merging conflicts) is better, and the traffic capacity of intersections is close to the traffic capacity without conflicts.

Sep 1, 2024

By M Lovitt, T Hewitt

The extraction of drawbells in Lift #2 at Northparkes Mines E26 orebody was achieved by single shot blasting, enabled through the use of electronic detonators. This paper discusses the designs considered at the time of the feasibility study and the various changes made to these designs prior to and during the construction phase of the Lift #2 block cave. Operational issues encountered are highlighted, as are ways in which these were overcome. The amount of personnel utilised to mine the drawbells is also covered. Lists of design and operational considerations to be used for drawbell extractions have been included.

Jan 1, 2005

By A-M Fleury

There has been much progress on the issue of acid drainage over the past 20 years; however, significant challenges remain. The International Network for Acid Prevention (INAP) is attempting to address them by globally coordinating acid drainage information sharing and research. INAP pursues three branches of activities: it links AD research, practice, and people; it organises, sponsors, and participates in regional workshops as a forum for technology transfer; and it instigates and funds key acid drainage research projects. Through these activities INAP is helping the industry deal with what is arguably its most serious legacy issue.

Jan 1, 2003

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 Q Fan

The steelmaking desulfurisation plays an important role in coal-based steelmaking route of blast furnace and BOF converter within the flow sheet of BF-deS-BOF. With the advent of H2-based ironmaking and steelmaking process, the transition flow sheet of DRI-Smelter-BOF has been assessed and developed by the steelmaking industry. What is the role of deS in H2-based route of DRI-smelter-BOF? This paper will present the influence of sulfur-containing iron ore on steelmaking desulfurisation and the leading role of EAF-smelter played in H2-based steelmaking route. The sulfur contents of iron ore vary considerably around the world and lower-grade iron ores with high sulfur are likely to be used for H2-based route, a considerable amount of sulfur that comes from DRI will report to the melt of EAF-smelter and the operating conditions of EAF-smelter also impact the sulfur content of the hot melt for steelmaking deS. The EAF-smelter of H2-based route is the focus of the steelmaking industry at moment, unfortunately, an industrial-scale EAF-smelter has been the missing link of the flow sheet of DRI-Smelter-deS-BOF, despite similar EAF-smelters being used for various applications of Fe-Ti and Fe-Ni processes. The latest progress is that several pilot-scale and industrial-scale EAF-smelters with reducing capability are planned for construction within next several years and low-grade Australia iron ores are certainly to be employed as basic feedstocks for H2-based route of DRI-Smelter-deS-BOF.

Sep 18, 2023

By Rayner J. G, Leckie J. F, Moorehead C. F

The Coronation Hill gold-platinum-palladium prospect is located in the valley of the South Alligator River (latitude 13'35'S, longitude 132'36'E), about 80 kilometres east of Pine Creek in the Northern Territory. Coronation Hill was one of thirteen sites in the South Alligator Valley at which uranium was mined between 1955 and 1964 after initial discovery by the Bureau of Mineral Resources in 1953. Most of the mines were operated by United Uranium No Liability. The Sleisbeck mine 25 kilometres south of Coronation Hill was operated by North Australian Uranium Corporation and the group of mines at Rockhole about 20 kilometres to the north-west of Coronation Hill was operated by South Alligator Uranium No Liability. The uranium mine at Coronation Hill produced about 26000 tonnes of ore averaging 2.6 kg/t U308 with an estimated average gold grade of 10.4 g/ gold. Gold was commonly associated with the uranium mineralisation and was recovered at the gravity treatment plant at El Sherana. Gold was also recovered in 1986 by Pacific Gold Mines Limited by treating the tailings from the Moline and Rockhole uranium leach plants at a CIP plant at Moline. With the completion of uranium contracts in 1964 mining in the South Alligator Valley ceased. Exploration for uranium continued in the area during the 1960s and 1970s with no success. The Coronation Hill Joint Venture (BHP Gold Mines Limited 45 per cent, Pioneer Minerals (Gold) Pry Ltd 45 per cent, Notgold Limited 10 per cent)carried out the first exploration specifically targetted at gold in 1984 with the drilling of five vertical drill holes which indicated high potential for a substantial gold resource at Coronation Hill with no associated uranium. The Joint Venture has sub- sequently drilled about 25000 metres of diamond drill holes at Coronation Hill alone. Analytical results from 1985 drilling established that platinum and palladium were associated with gold. An indicated resource of 3.49Mt at 5.12g/t Au, 0.21g/t Pt and 0.56g/t Pd has been calculated using a lg/t Au cut off.

Jan 1, 1991