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The phrase "Total-Energy" has, during the past few years, become widely used to describe a wide range of very different operations. However, if accurately described they all have one basic factor in common - energy usage is optimised with the prime mover being powered by gas or oil to generate shaft horsepower and the products of combustion being put to some use. The item which distinguishes a Total Energy system from any other engine or turbine driven project is that orate pains are taken to utilize the waste heat, whether this be in the form of exhaust gases and/or engine jacket ling water. n areas where grid supplies of electricity are readily available, the economics of most projects undoubtedly hinge upon the successful application of waste heat. However, there has been a growing awareness of other benefits, such as reliability of supply, which can be incorporated into the system. In particular these factors sway managements of hospitals and companies with complex computer facilities to examine closely the feasibility of Total Energy, Consequently, in America for example, where many systems have proved themselves the list of applications is wide - shopping centres, apartment blocks, office buildings, airline terminals, universities, schools, motels. And these do not cover the industrial sectors where the range is wider. The total number in North America is now approximately 500 and this to some extent-speaks for itself. In Australia, the real work involved in carrying out feasibility studies for Total Energy is only just beginning. 'in some quarters, the concept is not well received in that it is too new. Therefore, a typical approach is to play safe and wait until some other company has proved its operation "under Australian conditions". This is certainly a realistic approach when considering something revolutionary but as far as Total Energy.is"concerned all the individual components and sometimes combinations, (engines, generators, boilers, air-conditioning units) have been in operation for many years. The only innovation is that they are now all being brought together under one roof. This should not be forgotten when the question "where can I see something like this operating?" is asked.

Jan 1, 1970

Material hardness and environmental factors can limit or restrict conventional blasting techniques and this has led to advancements in the performance and efficiency of ripping. Not all materials can be ripped, however today's technology and experience can help make a reasonable prediction. A ripping versus blasting decision will depend on the total volume of material to be moved, the production capabilities and costs of the ripping tractor(s) and on the size and relative efficiency of drilling and Blasting.

Jan 1, 1995

By D Macklin, R Hammond, T G. Blenkinsop

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Base metal sulfides at the Currawong volcanic-hosted massive sulfide deposit in the Lachlan fold belt of Victoria, south-east Australia, were formed in the late Silurian, but D2 deformation of the deposit in the Devonian Bindian orogeny was responsible for structural repetition that created the resource. The primary sulfide lenses were stacked by reverse-sense shear zones within a volcano-sedimentary sequence dominated by dacitic intrusions and turbidites. Shear zones were localised along lithological contacts, including the margins of the sulfide lenses. The competent dacitic intrusions did not fold during D2; folding was restricted to the packages of metasedimentary rocks. Overturning occurs within, but not between, the metasedimentary packages. The overall geometry of the deposit is that of a duplex, but the detailed shape does not conform to idealised duplex types, probably because of post-D2 deformation. A significant complicating factor for understanding the deposit, and for resource evaluation, is the dramatic variation in deposit geometry along strike, which may also be due to post-D2 deformation. The present day configuration of the deposit results from constructive thrust repetition of what may have been a single ore lens and destructive along-strike disruption controlled by rheology.CITATION:Blenkinsop, T G, Macklin, D and Hammond, R, 2015. Rheological controls on the geometry of the Currawong volcanic-hosted massive sulfide deposit, Lachlan fold belt, Victoria, south-east Australia, in Proceedings PACRIM 2015 Congress, pp 469–474 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

The purpose of this paper is to outline the basic policy problems for good community relations programmes in the resource extraction industries of Papua New Guinea. The main focus of the paper will be on defining and analysing those problems which lie on the landowner side and which are still not widely understood within the resource extraction industries despite several decades of turbulent experience. Many of the companies operating in the resource extraction industries of mining and petroleum and gas have in recent decades adopted, by choice or necessity, 'good corporate citizen' policies. Some of these companies now pursue ethical business, environmental and community relations policies. Some have adequately funded and well-trained staff in their community relations departments. Although different industry sites scattered over Papua New Guinea show significant differences in their experience of social conflict, I argue here that a good deal of this variation has less to do with the differences between the companies' public relations policies and their effectiveness and more to do with the conflict causing features of indigenous society. Experience suggests that even a company well-equipped with good intentions, good policies and good staff may experience serious difficulties in maintaining good community relations in Papua New Guinea. Many of these difficulties, I argue, can be traced to causes that lie, essentially, within the structure of Papua New Guinean communities and in the customs and social relations of Papua New Guinean peoples. Accordingly the attention of this paper is focussed on the conflict causing aspects of Papua New Guinean society. It is true, to the point of being a cliche, that Papua New Guinean societies are oriented very strongly towards achieving consensus and social harmony. In this regard Papua New Guinean communities differ significantly from, say, Australian communities. My purpose here is not to denigrate this aspect of Papua New Guinean societies but, rather, to point out that the drive for consensus is driven by the desire to avoid its opposite, dissensus. This paper sets out to define the dissensual aspects of Papua New Guinean societies and my special interest is in those conflict producing aspects of Papua New Guinean societies that are most resistant to the mechanisms that are designed to create social harmony. A survey of the recent history of industry and community relations in Papua New Guinea indicates that there are three main factors present on the landowner side which are liable, separately or through their interaction, to cause difficulties. These factors are respectively generational challenge, social boundaries and custom variability and I shall discuss each of these in turn.

Jan 1, 1997

By Z Chang, S A. Mrozek, S Windle

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. It is important to understand skarn-porphyry transitions in order to use exposed skarns to look for associated and potentially larger porphyries. For such purposes, a good start is to understand the transition between porphyry and skarn in known deposits. In this contribution, we report the transition at Antamina, Peru, where skarns occur in and around a Miocene complex comprised of more than seven porphyritic intrusions. There are three types of skarn-porphyry relationships. The earliest intrusive phase, P1A, contains both endoskarn and porphyry-style quartz veins with secondary biotite halos. The porphyry quartz veins and endoskarns formed at the same time. Locally, the intrusion contains only endoskarn without porphyry quartz veins and is surrounded by exoskarns in carbonate wall rocks. In the third scenario, later porphyry (P2) intruding into P1A porphyry and skarns related to P1A contains abundant granular quartz veins and secondary biotite alteration but does not have significant endoskarn. The granular quartz veins also extend into earlier P1A skarns. The scarcity of endoskarn associated with P2 is related to the supply of Ca. The earliest P1A intrusion intruded into carbonates that supplied abundant Ca, therefore both endoskarns and exoskarns formed. In contrast, where the wall rocks of the later P2 intrusion are P1A or skarn related to P1A, there was little free Ca, therefore only porphyry-style quartz veins formed.CITATION:Chang, Z, Mrozek, S A, Meinert, L D and Windle, S, 2015. Skarn-porphyry transition – an example from the Antamina skarn, Peru, in Proceedings PACRIM 2015 Congress, pp 409–414 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

Computer software has been developed to link real-time information generated by underground mine ventilation airflow monitoring sensors into a network simulation program to undertake network simulations and allow interpretation of key system data and operational changes. Results were used in the development of a computerised monitoring and simulation system to provide immediate or real-time data on air behaviour within each branch of an underground mine ventilation network through linking of sensors to the ventilation network simulation software. The outcome of the project is an online system that can report changes in the mine ventilation system, allow causes of changes to be isolated and rectified, improve balancing of available air throughout the mine, allow improved approaches to regulator setting and dispense with much of the labour used for underground ventilation measurement. The work activities in both coal and metalliferous Australian mines have involved examination and modelling of regulators, software modification and considerable mine site testing and optimising activities. There is some discussion on approaches to control of flow through ventilation systems with increased information. New systems will be part of a total mine information management system. They will have to be cost effective and justified by gains in productivity. New systems will need to provide simulation of contaminant production such as diesels, vehicle heat, strata heat, radiation, blast fumes and other gases. More robust real-time ventilation simulation systems will be required. Personnel and vehicle identification and production tracking will be collected to provide integrated ventilation system monitoring and control. This paper examines a study to gain greater understanding of computerised real-time airflow monitoring and control within the mine production system to provide immediate simulated information in each branch of an underground ventilation network and to allow interpretation of key system data and operational changes. A case study implementing a real-time airflow monitoring and control is discussed. Approaches to control of flow through ventilation systems with increased information are discussed. The concept of a system that can be linked to or be part of a total mine information management system is developed. Such a system can form the base for mine automation that allows mines to incrementally and cost effectively implement monitoring and control to further seek gains in productivity.

Jan 1, 2005

This paper examines the broader implications of recent and ongoing changes in mineral resource managementå and reporting practices and the impact that these might have on mining companies. It is likely that an International Reporting Code will be developed in the near future, based on a number of National codes produced in recent years. However, this is only part of the reporting story, as an International Code brings with it a range of further issues to resolve. For the Code to be effective, there needs to be international recognition and perhaps licensing of Competent Persons and an expanded base of sponsoring professional bodies. Also, in an increasingly global business, shareholders, regulators and other interested parties need to know and understand the general processes involved in resource and reserve estimation and reporting in order to recognise companies that maintain the highest standards. There is a current trend towards greater scrutiny of company performance in a range of areas under the banner of corporate governance, and many changes are happening that will place greater disclosure burdens on all companies in the future. Good corporate governance means management of company assets for the benefit of the stakeholders. For a mining company, there is no greater asset than its mineral resources and reserves and directors are just as responsible for effective management of their mineral resources as they are for financial good practice. The paper looks at the relevance of corporate governance principles to mineral resource management and the changes that this could bring to the way that companies deal with regulators, shareholders, financiers and others. Finally, increased scrutiny and further regulation inevitably means greater effort by the industry and higher costs. Despite this the author believes that there are substantial offsetting benefits to be gained by companies prepared to take the initiative in improving resource management practices and communicating these improvements to shareholders. In order to achieve the benefits however, the industry needs to fully engage in the changes that are taking place û setting its own standards and working with the regulators rather than sitting back and being legislated against. Mineral resource reporting provides a good model of how this process can work and there will be other opportunities in the coming years as the industry seeks to develop best practice in mineral resource management. The author is an employee of Rio Tinto but wishes to point out that the views expressed in this paper are his own and not necessarily those of Rio Tinto.

Jan 1, 2002

By C J. Ptacek, J G. Bain, D W. Blowes

The passive interception and in situ treatment of groundwater using permeable reactive barriers (PRBs) has, within the past decade, become an accepted remedial approach to the control of plumes containing dissolved organic and inorganic contaminants. Since the first applications of the technology in the early-1990s, there have been several field-scale PRBs that have provided excellent treatment of dissolved metals in groundwater. Additional commercial applications and demonstration projects continue to be developed. Three field-scale applications and supporting laboratory columns have shown that several thousands of milligrams per litre of sulfate, more than 1000 mg/L iron, and several tens of milligrams per litre of other metals can be removed from groundwater by PRBs that promote sulfate reduction. The reactive materials, which incorporate various forms of organic carbon, promote microbially mediated sulfate reduction, the generation of hydrogen sulfide, and the subsequent precipitation of sparingly soluble iron and other metal sulfide minerals. Effective performance has been achieved by PRBs installed at a mine-tailings impoundment in 1995 (Sudbury, Ontario) and at an industrial facility (Vancouver, British Columbia). These PRBs have removed iron and other metals from groundwater. Similar materials were also used to create reactive layers within test cells directly in a tailings impoundment in 1999 (Timmins, Ontario) with the objective of removing iron and sulfate from the pore water before it migrates from the tailings impoundment. Zero-valent iron (ZVI) has been shown to provide excellent removal of chromium (VI) in a PRB, which was installed at the US Coast Guard facility in Elizabeth City in 1996, by reduction and precipitation reactions. Laboratory tests have also shown that ZVI reduces As(V) to As(III), which is subsequently removed from solution by co-precipitation with iron oxyhydroxides. In groundwater containing sulfate, ZVI and mixtures containing organic carbon can promote sulfate reduction and the subsequent precipitation of sparingly soluble arsenic and other metal sulfides. A trial PRB system was installed in 2001 and was shown to attenuate arsenic and other electroactive metals in groundwater at an industrial facility in northwestern Ontario. Basic oxygen furnace (BOF) slag, a waste material generated by the steel industry, has shown excellent potential for the removal of phosphate, elements such as arsenic and water-borne pathogens from groundwater in field and laboratory tests.

Jan 1, 2003

Teller Underground Mine was established to extract ore from the Middle Vale Reef located on the eastern flank of Telfer Main Dome.The mine is located below a 150 m deep open pit operation. The ore body is shallow dipping highly structured, and is a main aquifer in quite difficult ground conditions.In respect of these conditions it was determined to access the orebody using an adaptation of coal mining and hard rock mining methods, with support being achieved using a combination of island pillars, rock bolts and timber stalls.The paper will describe these methods in more detail, then discuss the successes and failures of these methods when put into practice. As well, it will detail several factors whose influences were found to be greater than previously expected and stress the importance of good geotechnical advice.

Jan 1, 1993

Facies associations in the Okiduse Volcanics, woodlark island, suggest that two major volcanic centres erupted synchronously during the Middle Miocene. These centres are referred to as the Watou Mountain Eruptive Centre and the Uvarakoi Caldera. The Watou Mountain Eruptive Centre, centred on Boganuse Mountain in the Okiduse Range, was a typical, moderate-sized composite volcano (or stratovolcano). The seq-uence is readily divisible into lava (Boganuse lava unit), breccia (Nikuben breccia unit) and epiclastic (Talpas sandstone unit) dominant facies, typical of composite volcanoes. These facies girdle Boganuse Mountain and they are interpreted to represent vent, cone forming and ring plain associat-ions, respectively. These facies indicate a reconstructed volcano of approximately 1,700m height with a basal diameter of 7km. The presence of limited exposures of intrusive associated with the vent facies (Kuike'beimmicrodiorite) suggests that the volcano is only partially dissected. The Uvarakoi Caldera is a felsic volcanic system contrasting with the mafic Watou Mountain centre.

Jan 1, 1994

By M Darvall And R Fare, D Dormer

The Argo Archaean lode gold deposit is hosted within a structurally complex shear zone system, 70 km south of Kalgoorlie, and 3 km west of the crustal-scale Boulder û Lefroy Fault. Argo is an active underground mine currently producing at a rate of 120 koz pa with a Probable and Proven Reserve as at December 2005 of 2.19 Mt at 5.94 g/t Au (419 koz), a reduction on the December 2004 Probable and Proven Reserve of 4.58 Mt at 5.74 g/t Au (845 koz). This Reserve is hosted in six separate gold bearing lodes within the Argo shear system. Presently, a further six subeconomic shears are recognised. The 2005 Reserve figure represents a reduction of 426 koz compared to the 2004 Reserve as a result of a thorough review of the geological interpretation/resource model, and engineering factors applied to the Resource/Reserve, and depletion due to mining. Year on year Resource/Reserve figures at Argo had gradually increased as additional information on the system became available and mining methods were increasingly resolved with early production. The portal for Argo underground mine was cut in June 2002 within the highly profitable Argo open pit. The proposed æAvocaÆ bottom-up mining method required extensive lead time between development and the commencement of stoping in April 2004. During development considerable additional complexity in the Resource was encountered. Additional structures were identified, and complex splay interactions affecting the geology impacted on development. Intensive concurrent exploration in the footwall to the main lode during this period was the main cause of the increase in the Resource/Reserve figures during early development. As development progressed, lower grade continuity was observed than was previously interpreted. At the same time, drilling of deeper portions of the deposit and subsequent reinterpretation of the geological model significantly reduced strike lengths of economic mineralisation. Radical changes to the mining methods were required to improve productivities and to satisfy geotechnical considerations. The changes altered the engineering factors applied, which resulted in a reduction in the Reserve figures.

Jan 1, 2006

By S KandT

The FalTmT iron ore deposits are located in the so-called æBirrimianÆ volcano-sedimentary complex that extends in a general NE-SW direction across eastern Senegal and part of Mali and Guinea. The rocks underwent folding and greenschist facies metamorphism, as well as various events of granitoid emplacement. The deposits form part of the DialT-DalTma Series of the Birrimian Supergroup and were subjected to contact metamorphism. The Fe-mineralisation occurs as primary magnetite within the metamorphic aureole. Supergene oxidation (martitisation) of this mineralisation produced the hematite-rich iron deposits that can be seen as prominent hills across the plains of this south-eastern corner of Senegal. BRGM of France and Miferso (SociTtT des Mines de Fer du STnTgal-Oriental) have conducted several phases of prospecting since 1957. Their aim was to delineate the hematite deposits and to assess the grade, beneficiation characteristics and marketability of the iron ore. A feasibility study by Fluor Daniel was completed in 1992. Results indicated that, at the time, the resource could not compete in the international arena in terms of size and accessibility. The growing iron ore market and additional available resources in the area now challenge the 1992 feasibility study results and put the old kid back on the iron ore block. The project faces some mining challenges, such as the amount of magnetite in the hematite product that will be acceptable to the market. Previous project evaluations only considered the secondary hematite deposits as economically viable. It is therefore important to accurately delineate the magnetite/hematite contact zone to optimise the resource tonnage. Project logistic constraints also exist in terms of railway access and harbour facilities. The resource is, however, well situated for the European iron ore market and aims to find a place in the rapidly expanding iron ore seaborne trade.

Jan 1, 2005

Exploration requires substantial capital, and is an extremely risky business (only 1 in 100 prospects ever becomes a mine). The average lead time, that is the time between discovery and production, varies from around two years for a gold mine, to 15 years for a lead/zinc mine. Since it takes years to find, prove and develop most ore bodies, exploration must be carried out years ahead of the depletion of existing deposits. Investors in exploration are exposed to risk for long periods before knowing whether they will receive a return on the funds invested. The risk, high-cost, uncertainty and long lead times involved in exploration make it an aspect of commerce that most managers and investors find difficult to rationalise or understand. Nevertheless, it is a given that the long-term survival of the mining sector depends on discovery of new mineral deposits, however the immediacy of the need to find or acquire new mineral deposits in order to compete and prosper in the industry is less well understood. This paper examines the commercial realities which underlie exploration for new mineral deposits. The first and foremost reason for exploration is to maintain or increase depleting ore reserves which are the asset base of mining, but there are other compelling commercial reasons for exploring, and these are: to maintain return on investment, to achieve growth or create wealth through discoveries which lead tonew mining ventures, to remain competitive in the industry, to diversify, and to control raw material source for mineral processing and/ormarketing ventures. Exploration is necessary for survival of the industry, and also for survival of organisations competing in the industry. The organisations which discover the best orebodies are in the best position to compete, and mining organisations which fail to find or acquire new mineral deposits rapidly become uncompetitive and unable to maintain return on shareholdersÆ investment.

Jan 1, 1998

Routine, in-pit geological mapping of highwall at Central Queensland Coal Associates (C.O.C.A.) deep strip mines has proved too slow for the increasingly greater highwall lengths which require mapping. This realiz- ation has encouraged the search for faster mapping methods and after trial of ground photographic methods has resulted in the adoption of interpretive mapping off stereo cover, oblique -- aerial photography. This entails using a Cessna 182 light aircraft flying at its slowest speed, the aerial meth- od finally employed consisting of two Vinten, air reconnaissance cameras mounted in parallel and simultaneously taking both colour and black and white photographs of the mine high- wall. The respective 1:500 scale enlargements produced from the 70mm format films combine to present the sharpest resolution attainable under the field conditions pertaining and such information on weathered material as only colour photography can fully render. Total costs for the aerial photography method are estimated to be about the same as those for conventional in-pit mapping. Whilst total costs are comparable, geo- logist's time for mapping a 10 km. length is reduced to less than half that for in-pit mapping (for Stage 1, fully accurate mapping) and accuracy and detail are greatly improved. A permanent, accurate record of overburden

Jan 1, 1981

With mining development on hold and other underground works in a slowdown, the development of nuclear wa te repositories takes centre tage on the American rock engineering scene. Three repositorie for commercial spent fuel-in salt, tuff, and basalt-are in the phase of site characterisation and conceptual design, and one pilot project for defense high-level wa te in salt is under construction. A repository design for crystal line rock has recently been postponed.Because of strict quality assurance requirements throughout design and construction, and because of the need to predict and ascertain in advance the satisfactory performance of the underground openings, much intellectual energy has been expended to analyse underground openings in the unusual circumstances of the repository environment. In the long term, these efforts will lead to an improved understanding of rock behaviour and improved methods of underground analysis and design. For the shorter term, a formalised ground control plan was developed, the principles of which may be applied to other types of projects.This paper summarises the status of underground design and construction for nuclear waste repositories and presents some details of the ground control plan and its individual elements.

Jan 1, 1988

The Myally Beds, Surprise Creek Beds and Mount Isa Group form the upper part of the Proterozoic Western succession of rocks in northwest Queensland. The latter two units are partly equivalent, and are important for their base metal content at Mount Isa and elsewhere. The arenaceous Myally Beds lie unconform- ably or disconformably below the Mount Isa Group and Surprise Creek Beds; they contain four mappable units which were deposited on a broad, shallow shelf washed by east-trending currents. Emergence of the Myally shelf initiated a series of parallel, possibly intra- cratonic, troughs to the east and west. In the east, the Surprise Creek Beds were deposited between the emergent shelf and base- ment rocks, and consist of a shelf and trough facies divisible into 7 and 10 units, respectively. Trough sediments are continuous north-south, and show turbidite character- istics; algal dolomite characterizes the shelf facies. To the west in the Mount Isa trough, an orthoquartzite facies, the Warrina Park Quartzite, defines the base of the Mount Isa Group. Hinge zones between the shelf and trough environments are marked by east-west facies changes, and provide a focus for later major north-south faulting. However, some penecon- temporaneous faulting near Mount Isa is best explained as complex post-depositional faulting of a disconformable sequence. Subsidence and deposition in the Mount Isa trough continued for a longer period than in the Surprise Creek trough, allowing accumulation of lead and zinc deposits in the upper half of the sequence. The Surprise Creek Beds appear equivalent to the lower half of the Mount Isa Group, and are probably not prospective for lead and zinc. Turquoise and possible other secondary copper minerals are widespread in the Warrina Park Quartzite and equivalents in the Surprise Creek Beds, and further investigation of these formations seems warranted.

Jan 1, 1974

Iron ore in the Pilbara Region of Western Australia varies in composition giving iron ore a range of densities. An accurate density figure of the material leads to accurate calculations of production throughput. Density studies of two separate iron ore mines were conducted in the Pilbara. Procedures and results are reported here.The Pilbara Region of Western Australia has a number of iron ore operations. Two mines have conducted density studies of their materials. The purpose for the studies was to determine an accurate in situ bulk density that could be applied to volume and tonnage calculations of the operation. It was identified that density was one culprit causing calculation variations. Density is an important figure used to estimate ore reserves, equipment requirements, production rates and indirectly costs and sales revenue. One study was conducted at Rio TintoÆs Robe River Mine based near the town of Pannawonica. Its Mesa J orebody is currently being mined and is a low-grade deposit of goethite and hematite (Burnham, 2003). A separate study was conducted at BHP BillitonÆs Yarrie Mine situated north of Newman and east of Pardoo. Its orebody consists of high grade formed by a supergene enrichment of cherty material and a burial metamorphism to produce hematite (Richardson, 2002). The method used to determine density was by large-scale samples using the pre-mining in situ volume of the material and the weight in tonnes after mining.

Jan 1, 2003

By Langham B. M

A chemical study of the petrographic components of Greta (Maitland) coal, carried out by the Metropolitan Gas Co. (Melbourne), has revealed an anomaly in the composition of the durain which was thought to warrant petrological investigation.The original study, by the Metropolitan Gas Co., extended over eight shipments of coal received during the winter of 1943.The percentages of the several petrographic components were eslimated by careful handpicking of large samples of each shipment, and analyses were made of the handpicked components, which were also tested as to their gas-making and coking properties.The results are summarised in Tables 1 and 2. At first sight the components of the Greta coal bear a general resemblance in composition to those of other bituminous coals of similar rank, apart from a notable richness in volatiles, which is a distinctive feature of Greta coal. The durain has a typically higher ash content, and lower volatile content than the clarain (Table 1); and the coking behaviour of the four components is typical (Fig. 4).When, however, the analyses of Table 1 are re-calculated on a dry, ash-free basis, an anomaly appears: the clarain and the durain, on this 'pure coal' basis, have practically identical compositions, with the durain containing a slightly higher proportion of volatiles than the clarain (cf. Table 3); but the tar yield of these two components is very different (Table 1). Re-calculated on a dry, ash-free basis, the yield from the clarain is 18.9 gallons of tar per ton, while, that of the durain is 29.0 gallons per ton. The gas derived from the durain is correspondingly richer in illuminants (CH etc) and poorer in hydrogen than that from the clarain (Table 2), and is also notably richer in nitrogen.That the composition of the Greta durain is consistent is proved by the analyses of Table 3, in which the compositions of the respective durains and clarains of eight separate shipments of coal are compared. In most bituminous coals, the durain contains several per cent less volatile matter than the associated clarain, and high volatile content in a durain usually indicates a durain rich in spores.

Jan 1, 1947

By Lacy JC

Human habitation of the Pacific Rim began when mankind began migrations out of its place of origin in the Rift Valley of Central Africa c. 4million years ago. This migration was erratic and largely controlled by advances and retreat of the various Ice Ages which, while limiting advances in areas of intense cold, at the same time aided migration thro-ugh the creation of land bridges as ocean levels declined during periods of glacial advance (Fig.l).Mankind began its trek to the Pacific from Africa across India then north into southern China and south into Indonesia (Fig.2). In part, these migrations stimulated early technological develop-ments to fulfill needs and adapt to environmental conditions; thus, these nomads developed stone and bone tools, animal skin clothing and the use of caves and other simple shelters. The earliest evid-ence of mankind's use of fire can be found at Zhou-koudaian near Beijing, c.400,000 BP.From China, the completion of the Pacific Rim's population can be attributed to the last Ice Age that dropped the ocean level by more than 300 feet and created land bridges about 40,000 BP allowing migration across the Bering Strait into Alaska and to Australia from Indonesia. The American migration reached Mexico about 30,000 BP, and by 6000 BP the occupancy of the Pacific Rim was complete when the first human settlers reached the southern tip of Chile.

Jan 1, 1990

Fundamentally, the development of a minerals processing project is a very risky enterprise. Most mining companies do not have sufficient financial resources to undertake significant projects and hence have to undertake external financing. Indeed, most resource companies understand the high risks associated in developing their projects and therefore, wish others to share in the risks. Most merchant banks, on the other hand, are searching to find suitable resource development projects in which they can share their risk and also share a large proportion of the ærewardÆ. To resolve this issue a Feasibility Study is completed by the project developer and assessed by the merchant bank often with the assistance of an æIndependent EngineerÆ (IE) who assesses the validity of the development proposal. Generally speaking, unless the Feasibility Study has been prepared improperly, the technical aspects of most mineral projects are reasonable. Some of the more recent so-called æhigh techÆ projects are exceptions but these still do not present major technical mistakes or misconceptions. p> In most cases, the major criticism the IE presents after discussing the validity of the ore reserves focuses on production plans, capital costs and operating costs. Of these three parameters the production plan is one in which owners tend to be far too optimistic and financiers, until recent years, have not taken a position. The most critical part of the development plan is the ability of the project, as designed, to attain the required design performance and, even more critically, the ability of the owner to reach and sustain this level of production. In short, how long should the æramp-upÆ be planned to take? Financiers have become more circumspect and are now taking a more conservative view of new project performance by factoring into their project financial analysis longer periods of ramp-up, higher capital costs and higher operating costs. However, these financiers can also be part of the æproblemÆ if they become overly conservative. This paper attempts, by way of case studies available from the public arena, to identify the pitfalls the project owners can meet and possible means of avoiding the disastrous financial conundrum whereby the second or third æownerÆ is the company that reaps the rewards initially extrapolated. The paper briefly discusses this problem by referring to projects known to the author and including previous studies that looked at this very problem. It is emphasised that many of the opinions stated within the paper are strictly those of the author and could be subject of much debate.

Jan 1, 2003