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By S Joyce, Z Agioutantis, D van Zyl, D Shields

Over the past 15 years, the mining industry has begun to incorporate the concepts of sustainable development and sustainable mining practice across the life cycle of mineral operations. This requires addressing economic issues, community impacts and concerns and environmental protection, and is captured in part by the phrase ‘design for sustainability’ (McClellan et al, 2009). Over the same period, the industry has seen a gradual decline in ore grades for many mineral commodities. As a result, large volumes of tailings and mine waste rock are being produced around the world, and it is expected that the annual production volumes of these materials will increase, even if there is not a significant change in the demand for materials.Another related thread of change has been the realisation that societies need to move away from linear economies (raw materials, production, consumption, disposal) towards more circular ones. This will help societies become more resource efficient, which is defined by the United Nations Environment Programme as reducing the total environmental impact of the production and consumption of goods and services, from raw material extraction to final use and disposal. The goal is to create more with less and deliver greater value with less input. Circular economies require thinking in terms of the waste hierarchy (reduce, reuse, repurpose, recycle, recover, landfill).The challenge is that the waste hierarchy was originally designed to address embodied mineral content in products rather than mine waste and tailings generation. It will need to be reconsidered in a mine life cycle context, focusing on a value-based conception of waste (Van Ewijk and Stegemann, in press).In parallel to these changes, it has remained an imperative in the mining industry to dispose of these waste materials as economically as possible while protecting the environment. Single handling of these materials has been the main target, which reduces the life cycle costs of their management but may make reuse of waste and tailings technically more difficult or economically infeasible.This presentation explores a rethinking of the large volume earthen material waste issue at mines. The underlying theme is that some or all of these materials can be valuable resources for the future that can positively contribute to sustainable development. These resources can offer economic gains to firms, communities and societies; contribute to environmental well-being; enhance social interactions with the previously mined landscape if handled properly; and, with proper policies in place, reduce governance commitments. Each of these topics will be briefly explored. This will be followed by a discussion of approaches to manage design and operations to allow future resource recovery.CITATION:Van Zyl, D, Shields, D, Agioutantis, Z and Joyce, S, 2015. Waste not, want not – rethinking the tailings and mine waste issue, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 7–10 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By Hindmarsh G

The colliery is owned by the BHP Collieries Proprietary Ltd., the principal shareholders being the Broken Hill Pty. Company Ltd. and Hebburn Limited.It is situated due west of Newcastle and 6 south-east of Cessnock, N.S.W., and is conneeted by 36 miles of railway to the port of Neweastle. Of this mileage, 3 miles are owned by the Company, 3 by Hebburn Limited, 9 by the South Maitland Railways Ltd., and 21miles by the Government Railways.The seam worked is known as the Main Greta Seam of the Greta Coal Measures and is on the southern slope of the Lochinvar anticline.At the shaft, the seam is 1190 ft. below the surface, and the section of the coal measures is:-Upper or Main Seam, . 24 ft. 0 in.Conglomerate and shale 70 ft. 0 in.'Middle Seam 8 in.Conglomerate 25 ft. 0 in,Bottom Seam 1 ft. 2 in.These lie between two marine measures, and are the lower coal series of the permo-carboniferous period.Only the upper seam is workable in this area, the lower seams being too thin for eompetitive working. The section of the workable seam at the shafts is as shown on Fig. 1.Unfortunately, only the lower 12 ft. 5 in. of the seam is saleable.

Jan 1, 1935

In order to meet the increasing demand for coal for their Newcastle Steel Works, the Broken Hill Pty. Co. Ltd., on June 5, 1937, approved of a scheme to sink a tunnel to the Victoria Seam at their Burwood Colliery. This seam was virgin at this locality and lay nominally horizontal at a depth of 320ft. vertical from the surface.For the purpose of despatch of the coal produced it was decided that the tunnel be equipped with a rubber belt conveyor system.This was a comparatively new departure in Australia, and, indeed, was one of the first installations of its kind in the world, designed to raise coal from considerable depth by this means. Later the tunnel was extended to the Borehole Seam, which lay nominally horizontal at a vertical depth of 600ft. from the surface. The whole installation is the subject of this paper.In planning a project of this kind, consideration had to be given to the following:-1. Location of tunnel with regard to existing surface railway sidings and shafts.2. Ultimate tonnage required.3. Width and construction of belt.4. Speed of belt.5. Inclination of belts.6. Number of belts and design of equipment.7. Cross-sectional area of tunnel.8. Inclination of tunnel.9. Surface drainage.10. Type of equipment for drifting the tunnel.11. Method of ventilating the tunnel during sinking.After the general layout and design of the scheme had been prepared it was decided that tunnel drifting would begin immediately and that the belt installation, together with the feeder plant, would be detailed and manufactured by the time the drift...

Jan 1, 1947

By E Claridge

There are a number of major infrastructure tunnelling projects currently underway or proposed in New Zealand, including construction of new road and rail facilities and the refurbishment of existing road tunnels. These new projects have triggered a rethink of traditional practices in underground fire and life safety and local regulation.While there is a current surge in activity, tunnels have been a signifi cant part of New Zealand’s transport infrastructure for over a century. Despite this background, the new projects commonly face challenges that are symptoms of a national regulatory environment that has aspects that are inappropriate for underground environments. There are inconsistencies in local regional regulation and an absence of national guidance and standards relating to tunnel design. Historically, New Zealand has looked across the Tasman for guidance. Although recent overseas tunnel designs present learning opportunities, the adoption of international best practice and standards may not necessarily address local expectations or needs.This paper explores a number of specific matters affecting the design of road and rail tunnels in the New Zealand context, namely; the Building Regulations and associated local consenting processes and parties, and the responsibilities and needs of the New Zealand Fire Service.The discussion highlights the importance of a collaborative approach involving the designer, asset owner, regulators, emergency services, and other parties, and ensuring up-front clarity in design responsibility and ownership of residual risk.

Mar 8, 2011

By D Drinkwater

In 2009, Peter Munro and Peter Tilyard examined the “human capital” in the mineral processing sector in a paper entitled Back to the Future (Munro and Tilyard, 2009). One of their major concerns was a general decline in technical skills and process knowledge, exacerbated by lack of appreciation of the impact this can have on process plant performance and, ultimately, profitability or sustainability of the industry. There are many reasons for this decline, not least of which are the work schedules of today’s metallurgists which have a very different balance between technical and non-technical responsibility than those in the past. However, a shift towards a more technical focus has potential to deliver a range of benefits for industry at large and for the individuals in it This paper discusses some options for development of core metallurgical and process engineering skills that can be used by graduates, employers and training providers.Key skills are identified and mapped against available opportunities for development, such as existing graduate programs, on-the job training and external courses. The authors also review a number of past and present high-quality graduate development programs, including the graduate development program in place at Mount Isa Mines in the 1980s and the Anglo Platinum Graduate Development Program (AGDP) currently operating in South Africa.

Aug 8, 2011

By D A. Sketchley

The Merlin Zone, a 2008 high-grade Mo-Re discovery, is a part of the Mount Dore Deposit in the Eastern Succession of the Mount Isa Inlier in Queensland, Australia. Hosted by carbonaceous metapelites and phyllites, the Merlin mineralisation comprises molybdenite veins, breccia infillings, stylolitic fracture fillings, and disseminations. Because rhenium is geochemically similar to molybdenum and commonly associated with it, global production of rhenium has been mostly a by-product of molybdenum refining. The high-grade rhenium in the Merlin Zone is an exciting discovery that is expected to become a direct source of rhenium. At the time of discovery, quality assurance (QA) procedures for rhenium were not in place at the Merlin Zone; therefore, they needed to be developed.The Merlin Zone was discovered using reverse circulation drilling, which led to concerns about molybdenite loss due to poor sample recovery. The twinning of the discovery hole with diamond core demonstrated a two-fold increase in molybdenum grade over several tens of metres. Consequently, the resources of the Merlin Zone were defined using assays from diamond drill core.Early analytical work, which was initially done only for molybdenum, comprised geochemical analysis with an aqua regia digestion, which have poor precision and can be biased low. Although initial testing for rhenium used similar procedures to those for molybdenum, a scarcity of commercial rhenium reference materials led to a validation process using neutron activation analyses and different digestions. This resulted in introduction of four-acid digestion assays, development of matrix-matched reference materials, and improvements to the quality of molybdenum and rhenium assays for reporting resources. Coarse and pulp duplicates were used to check for sampling bias and to ensure that levels of precision were adequate for the style of mineralisation and analytical methods. In addition, the direct and consistent geochemical correlation between molybdenum and rhenium provided another method for checking analyses.

Aug 22, 2011

The mining industry has expanded significantly in the Pacific Region over the past two decades through a mix of new developments and brownfields expansions of existing operations. Despite this overall success there are also a number of well publicised examples of less than successful minerals ventures. These problem developments highlight the fact that success cannot be taken for granted and that rigorous planning and attention to detail is essential. The dominant growth has come through expansion of existing businesses, notably alumina, iron ore and coal, achieved through both efficiency gains on existing plant and step change capacity additions such as new mines and/or expanded processing plant. This expansion has largely been linked to increased market opportunities. The major issues are the quality and extent of the host resource, achieving the market targets, and the efficiency of the expansion effort. There can be also a range of site specific issues which need to be addressed. The development of new greenfields operations is often more complex as it can bring a wide range of new issues. Depending on the nature of the development, and the companies involved, these can extend from initial financing through to obtaining a market position. Incorporating major new technology and/or establishing infrastructure and attracting staff to remote locations can also add significant challenges. This paper outlines many of the critical factors which need to be considered prior to proceeding with major expansions or greenfields developments. These will be linked to a number of developments in the region over the past decade.

Jan 1, 2004

By R C. Morris

Two major types of economic secondary iron ores occur in the banded iron formation (BIF)-rich Hamersley Province of the Pilbara, Western Australia:dominant BIF-hosted bedded iron deposits (BID)detrital ore deposits (DID sensu lato), which are mainly hosted in the three province-wide Cenozoic sequences that include coeval non-ore sediments and comprise:a. the major Miocene, fluvial channel iron deposits (CID)b. the lesser Eocene and Pliocene detrital iron deposits (DID sensu stricto).Striking differences exist between the massive CID resources and the much smaller underlying and overlying DID. CID are essentially riverine alluvial ooidal rocks with abundant small fossil wood fragments and variable iron peloids, but with only extremely rare recognisable lithic remnants. The original matrix is typically ramifying layered goethite. Eocene DID are mainly alluvial with minor pisoids, whereas Pliocene–Quaternary DID are dominantly coarse colluvial gravels, both derived from and largely retaining the original textures of BID, hard cap or variably ferruginised surface BIF. The colluvial DID matrix is typically ferroan-aluminous soil, resulting in canga where replaced by goethite, which may be dehydrated to hematite by exposure. The Cenozoic deposits occur in two dominant geomorphological environments: the southern Marra Mamba to Brockman Iron Formation strike valleys containing all three Cenozoic sequences and the much later northern Brockman Iron Formation plateau valleys that include only the Miocene and Pliocene sequences. The Cenozoic detritals formed in different climatic regimes, with an extended dry period forming a prominent province-wide dehydrated carapace on the Eocene DID. The Miocene ‘optimum’ followed with its thick scrub-covered deep regolith that produced the fossil wood-rich CID and was succeeded by the arid cool period of the Oakover limestone/calcrete. A major renewal of exposure and erosion in the Pliocene resulted in the extensive iron gravels of the Pliocene–Quaternary.CITATION:Morris, R C, 2015. The Cenozoic detrital iron deposits of the Hamersley Province of Western Australia – a tribute to Mal Kneeshaw, in Proceedings Iron Ore 2015, pp 319–326 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By A C. Robertson

World urban expansion puts constraints on the available land surface area of our major cities both for accommodating people as well as providing infrastructure and services whilst at the same time attempting to preserve the remaining natural environment. Whilst consideration is often given to underground planning for private and public transport infrastructure, the author is of the opinion that the current lack of underground planning of our cities that are suitable for underground development will have major long implications when finally the need for underground space planning is critical and ultimately recognised. This paper identifies the need for our city planners to integrate surface planning and underground planning as a ‘total planning solution’ where the city plan incorporates the elements of underground space planning as identified in this paper. Investigations by the author reveal that there are very few cities in the world that actually incorporate underground space planning in their city plans. The author uses the City of Brisbane as a case study for the potential introduction of underground space planning as part of the city plan. Despite efforts by the author to include the planning concept of underground commercial development in the latest Brisbane City Plan 2014 as well as four underground space workshops in Brisbane over the past 20 year through the Australasian Tunnelling Society (ATS), underground space planning for the City of Brisbane, apart from infrastructure projects, is not considered of significance to the City of Brisbane.CITATION:Robertson, A C, 2014. Commercial underground space – planned development for the future, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 513–518 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By W J. Shaw

Mining operations must become more predictable to overcome the volatility that has characterised the mining industry. Comparisons of production against predictions will become more consistent as mining operations merge and expand, as personnel move from site to site, and as public reporting of reconciliations becomes more prevalent. More consistent approaches are already being seen in the industry using the terminology used in this paper and elsewhere.Examples are provided that show how use of the waterfall chart as a reconciliation management tool can provide objective analysis to improve practices.Geometallurgical modelling is becoming more useful and will continue to do so as we move from a few bulk samples to better interpretation of material properties from geological mapping and drill sampling. Reconciliation has evolved to the stage where predictions of geometallurgical properties to optimise mill performance, and of geotechnical properties derived from better 3D geological models, should also be reconciled.CITATION:Shaw, W J, 2014. Reconciliation – outcomes and expectations, in Proceedings Ninth International Mining Geology Conference 2014 , pp 123–128 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

The importance of the accurate determination and interpretation of the bulk density and porosity of a given iron ore deposit is very often disregarded or neglected. Large amounts of time and money are spent on delineating and testing orebodies, and yet one of the most important factors in resource evaluation is sometimes estimated or, at best, determined from existing data from similar deposits. The Thabazimbi and Sishen South iron ore deposits are two well-known economical occurrences of high-grade iron ore in South Africa. Both these deposits formed as secondary enrichment of banded iron formation lithologies. Ongoing density studies on both these deposits are underway and results thus far proved very effective and necessary. Small-scale methods are used to determine average values for different ore types on both deposits. These values are used in resource estimation and geophysical interpretation.

Jan 1, 2007

By L S. Barbour, M K. Meiers

Soil covers for mine waste are subject to changes in structure as a result of root development, and wet/dry or freeze/thaw cycling. The purpose of this study was to evaluate the changes in the hydraulic conductivity of three non-compacted clay covers over time. The covers are located on a sodic/saline overburden fill (30-Dump) at the Syncrude oilsands mine in Fort MacMurray, Alberta, Canada. Monitoring of these covers for temperature, matric suction, and water content by the University of Saskatchewan has been ongoing for more than three years. The three covers (D1, D2, and D3) were constructed in 1999 and are 50 cm, 35 cm, and 100 cm thick. The covers are comprised of a surface layer of reclaimed peat/mineral mix over a secondary reclaimed mineral soil (glacial till or glaciolacustrine clay), placed over a sloping shale surface. Field measurements of hydraulic conductivity within the secondary layer were obtained using a Guelph Permeameter during the 2000, 2001, and 2002 summer field seasons. Repeated measurements were made within the D1, D2, and D3 covers at depths of approximately 40 cm, 30 cm, and 60 cm, respectively. The values of hydraulic conductivity for the covers were similar to each other during each of the field study seasons. The mean hydraulic conductivity of the secondary layer increased every year: 2.5 + 10-6 cm/sec to 2.1 + 10-4 cm/sec to 4.3 + 10-4 cm/sec from 2000 to 2001 to 2002. Soil temperature data shows that one freeze/thaw cycle occurred each year at the measurement depths.

Jan 1, 2003

Over the last ten years geological and mining software products have evolved greatly. Software companies developing such products have focussed almost exclusively on the development of technical aspects of the applications, addressing geological, ore reserve estimation and mine planning problems. These specialist applications, and the many other new technologies that are being developed by a myriad of niche developers, are an essential part of todayÆs hi-tech mining operations. Technology is also being used in many other areas to improve the mining process and there is no doubt that tremendous advances are being made in all these fields. Yet there is something missing. The manner in which the technologies are used and implemented has led to the creation of many independent and inefficient æislands of technologyÆ where a variety of products from different vendors are used to address different, but related problems. Problems occur with unreliable information, data duplication, data redundancy and transferring data between applications that may be incompatible or even run on different computer platforms. These problems impede the flow and availability of information and hamper day-to-day decision-making by mine management. A solution to this problem is to take a holistic view of all the various technical applications and incorporate them into a single information technology solution. This solution must encompass all of the information requirements of a mining operation and must provide facilities that address much of the modern thinking about mine management, including strategic mine planning, value management, key performance indicators, and maintenance of a mineral balance sheet. Gemcom is developing an Integrated Resource Asset Management System (IRAMS), which is an enterprise-wide integrated computer system that encompasses various applications typically found at a mining operation. The core component of the system is a common, open, industry standard database that can be shared by many users from each of the different departments at a mine. Around that central repository are the primary applications that provide the mine with information it needs to operate. Ensuring that the information is reliable, accurate, shareable, timely and consistent will eliminate many inefficiencies, and provide significant benefits to mining companies. In turn these benefits will lead to significant improvements in decision-making, productivity and profitability for the operation. The initial version of the IRAMS system is currently being implemented at the De Beers Venetia Mine in South Africa. The system is being built around a core repository using the Microsoft æBack OfficeÆ architecture, and incorporates key technical applications from Gemcom, Whittle, De Beers Technical Team, Wenco and JKTech. The benefits of enterprise-wide systems have long been recognised in the commercial arena and enterprise resource planning (ERP) systems such as SAP, JD Edwards and MIMS are becoming commonplace in the mining industry. The more forward looking software developers and mining companies realise the need for efficient management of the information gathered during the mining process and can see that the concepts used in ERP systems apply equally to the technical applications as they did to commercial applications. The use of IT in the mining industry has expanded tremendously over the last five years as enabling technology and management acceptance has become more prevalent, and there is considerable room for dramatic growth over the next five years. The evolution of geological and mining software has now reached the stage where mines will yield the greatest returns by integrating the applications used in each area of their operations.

Jan 1, 1999

By J Palise

As cities become more populated and the need for tunnelling increases, we continue to dig deeper urban tunnels in more challenging ground conditions. At the same time our expectations for durability and long-term performance are increasing.It has become increasingly apparent in recent years that repairing water leaks in tunnels can be very costly and unplanned infiltration can cause undesirable outcomes for long-term maintenance costs, structural durability and environmental impacts. For this reason, tunnel constructors are investing more time and effort upfront into drainage and waterproofing systems.Tunnel membrane systems are becoming accepted as a necessary part of tunnel construction, however the knowledge surrounding selection of appropriate systems, design detailing and installation methods has not increased at the same rate. Currently Australia relies heavily on International Standards from Europe and the United States with no immediate program in place to establish our own locally relevant industry standards.This paper gives an overview of where the industry in Australasia is heading in terms of adopting relevant standards. Current basic waterproof detailing options for drained and undrained tunnels with success and failure of various methods are also addressed. Finally we look at the Brisbane Airport Link as a case study for how tunnel waterproofing contract methods, design and installation issues are being addressed in context with recent projects including the Epping to Chatswood Rail Link in Sydney, Auckland Northern Gateway Tunnel, Eastlink Tunnel in Melbourne and Sydney City West Cable Tunnel.This paper’s primary objective is to propose guidelines for how tunnel waterproofing could be implemented on large infrastructure projects in the future and to map a path for preparing and introducing a ready to use document for selecting appropriate tunnel membrane and drainage systems whilst implementing detailing methods which are appropriate for local conditions.

Mar 8, 2011

By P B. Schwann

The commonly accepted genetic theories of Pilbara iron ores and Woodie Woodie manganese ores have often presented them as quite unique. This apparent uniqueness is not confined to just iron and manganese, but is also seen in gold and copper deposits in Western Australia. The published material on iron and manganese ores would seem to have either a quite complicated genesis or none at all. An alternate theory for the origin of these deposits is presented which involves a protore with simple oxidation and pH controls with hydrothermal fluid sources from the diagenesis and dewatering of the underlying strata. This theory explains the distribution, thinning, cold dolerites and very high concentrations of deleterious minerals observed in these deposits. This genesis system is also related to the systems that deposit hydrothermal gold and copper in sediments in the region.This paper presents the author’s observations, sampling and mapping after several decades studying and exploring for the minerals in Australia and locations overseas. All of these theories were developed with (or in spite of!) the guidance of Mal Kneeshaw, but would never have seen the light of day without him and the others presenting here. It is not what I would call scientifically polished, and possibly deserves more detailed studies; it is, however, presented as a discussion paper.CITATION:Schwann, P B, 2015. Related genesis for iron, manganese and gold-copper ores in Western Australia, in Proceedings Iron Ore 2015, pp 327–336 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By D J. Williams

The approach to the disposal and storage of mine tailings is slowly evolving. Tailings disposal has been based on minimising short-term capital and operating costs, with rehabilitation costs discounted by the application of a high discount factor in a net present value approach to accounting. This has led to the widespread adoption of surface tailings storage facilities (TSFs) to store slurried tailings delivered by robust and cheap centrifugal pumps and pipelines. Depending on the site climate, rate of rise of the tailings, nature of the tailings and the extent to which supernatant water is removed from the surface TSF, the tailings may or may not dewater, densify and gain strength. High rates of rise of dilute tailings to a facility used to store both tailings and supernatant water results in a wet, low-density, soft tailings deposit that not only occupies a large storage volume but also presents rehabilitation difficulties. A low tailings density results in high containment wall costs, very high rehabilitation costs and a low potential for future land use or ecological function. Overall, the cost of slurried tailings disposal, thought to be low, is actually high. However, low rates of rise, even of dilute tailings, in a dry climate with efficient supernatant water removal can produce a dewatered, high-density, stiff tailings deposit that may occupy a large footprint but to shallow depth that is relatively easy to rehabilitate. There are advantages in dewatering tailings in the processing plant to recover process water and chemicals, facilitate tailings disposal in a more solid form and facilitate rehabilitation. However, the cost of dewatering in-plant can be high, and the process water may not lend itself to reuse. There are also advantages in removing supernatant water to facilitate solar and wind drying of exposed tailings, although water is lost to evaporation and the dried tailings may best be harvested prior to inundation by fresh tailings or rainfall run-off. This paper discusses the background and trends towards the elimination of conventional surface slurried TSFs, with examples presented of the management of black coal and other tailings, including those that are clay mineral-rich.CITATION:Williams, D J, 2015. Towards the elimination of conventional surface slurried tailings storage facilities, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 11–24 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By R H. Knight

Uncertainty in prediction and modelling of geological (physical) ore continuity in geometrically complex ore deposits is a key risk factor in mining. Reducing geometric uncertainty of hard-boundary ore/waste contacts and related geological features improves the efficiency of local mineral resource estimation and reserve calculation, mine/stope planning, ore control and in-mine exploration. Detailed underground mapping of serial-level drives provides a continuous record of the characteristics and contact configuration of ore, as well as crucial ore-related geological features that are required to resolve geometrical variability when closely spaced drilling proves inadequate or is cost-prohibitive. The mapping-based approach described in this paper re-establishes the focus on the geology of the orebody by incorporating high-value, detailed geologic mine mapping information. Mapped ore-related configurations and relationships, recorded on a succession of faces or on a series of levels, provide the basis for 3D interpolation and extrapolation of the local geologic continuity of an orebody. Correlative points representing locations of key ore-related geologic features on each face or level are linked by 3D polylines or trajectories forming a coherent geometrical framework. The coherent progression of geometric changes mapped by these trajectories reveals the overall ‘dynamic’ of the geometrical framework, as well as the spatial tendencies of its geological constituents. Distinct sets of ore control trajectories are selected from within the framework and are used in the construction of alternative geological ore continuity models. As mining proceeds, alternative models are evaluated, and are then either refined or rejected. The geometrical framework is used to evaluate theoretical models and practical heuristics, focus exploration targeting and inform and guide all aspects of mine geology in active mines. This approach also lends itself to analysis of global ore continuity in the re-evaluation of mature or abandoned mines. Its use is particularly effective in geometrically complex orebodies such as the West Branch orebody and the orebodies of No 2 mine of the Balmat-Edwards-Pierrepont zinc district, which are used to illustrate the method. CITATION:Knight, R H, 2014. A mapping-based approach to geological continuity prediction using examples from the Balmat-Edwards-Pierrepont Zinc District, St Lawrence County, New York, USA, in Proceedings Ninth International Mining Geology Conference 2014 , pp 65–76 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

The development of Mount Isa Mines Limited power supply is traced through the history of the mine operations. As would be expected, growth of the power supply system follows closely the increase in mine output, although it will be seen that total kWh. produced per ton milled shows a considerable reduction in later years when the mine output showed a more rapid rate of increase. That this reduction is not more marked is possibly due to the increased community and Shire Council power usage per head of population.INTRODUCTIONThe geographical position of Mount lsa, far from any large regional power supply Authority, dictated the policy that the Company be responsible for the production and suppiy of all power required for the plant operation. The Company also, in November 1937, accepted responsibility for the supply of a part of the power requirements of the township of Mount Isa. The history of power supply to the Mine may be divided into several phases.1. The supply Of lighting and power during the first plant construction period 1929-1931.2. The construction of the first section of the Mines Power Station, comprising Nos. 1 and 2 turbo alternators and boilers.3. The addition of No. 3 turbo alternator and boiler.4. The addition of No. 4 turbo alternator and boiler.5. The addition of No. 5 boiler.6. The addition of a. 2 turbo blowers for air supply to the Copper Smelter converters; b. 1 turbo blower for air supply to the L.ead Smelter; c. 2 turbo compressors for compressed air supply to the Mine and surface plant.

Jan 1, 1961

By E Werner, B R. Leavitt

The chemistry of acidic mine drainage discharging from flooded coal mines is commonly reported to improve with time after flooding. This investigation describes a 18-year dataset of post-flooding water chemistry for a below-drainage underground coal mine within the northern Pittsburgh coal basin (Pennsylvania, USA). The Montour mine is a 5650-hectare below-drainage coal mine of maximum 260 metres depth. Montour was closed in 1980 and flooded to within 38 metres of land surface within 4.8 years. Pumping averaging 210 L/s was then employed to maintain water levels at this elevation. The flooded proportion of the mine (by volume) at full flooding was 56 per cent. The shaft where water was pumped from Montour for water control is located about 70 per cent of the distance between the mine water table and the back of the mine ù that is, it is close to the back of the mine. The residence time (total water volume at flooding divided by pumping rate for control) is estimated at 5.6 years. Time series of chemical analyses show three phases of chemical behavior in post-flooding discharge. In Phase I (zero to two years after flooding), iron concentrations were high and reached their maximum (1100 mg/L). In Phase II (two to four years after flooding), a transition was begun to alkaline conditions, with decline in iron and other solutes. In Phase III (>4 years), net alkaline conditions began, with iron concentrations declining exponentially to 50 per cent of mined volume. This attainment of net alkalinity in this case may have also depended on abundant calcite in overburden extended up to 30 m above the mine floor.

Jan 1, 2003

By D Hume

During 2001 the Ridgeway Gold Mine, driven by company initiatives and recent NSW legislation (General Rule 2000), developed and implemented Major Hazard Management Plans to control significant hazards identified at the underground mine. The paper presents the objectives, issues, outcomes and process involved in the development and implementation of the plans at Ridgeway. The sharing of the experience gained and an overview of the intended way forward will offer a valuable insight for other mines considering embarking on a similar journey.

Jan 1, 2002