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By Resta S. A

Energy Resources of Australia Ltd - Ranger Mine is located about 255 kilometres east of Darwin in the Alligator Rivers Region of the Northern Territory. The Ranger project is surrounded by Kakadu National Park which is on the UNESCO World Heritage list. . Ranger Mine operates the largest uranium mine and processing plant in Australia. It is designed to produce 3000 tonnes of uranium oxide per year, but presently is producing a little less than one half that figure due to the depressed uranium market. The safety performance of the employees and Ranger as a whole continues to improve. The lost time injuries (LTI) have significantly reduced from 74 in 1985 to five in 1994. The total days lost due to LTIs have gone from 1543 to 14. These significant improvements have reflected directly on workers' compensation premiums in which a four-fold reduction has occurred. It is estimated that the actual monetary saving to the company is about $1.3 million per year and directly reports to the profit of the company. There is also an obvious and significant reduction in the less quantifiable costs such as the suffering of the injured employees and cost to society. The paper will review the various initiatives introduced and assess their effectiveness. Performance improvement is primarily dependent on the commitment, introduction of various initiatives and the subsequent change in workplace culture.

Jan 1, 1994

TSG Consulting works with many of the major global mining companies using simulation modelling as an integral component in their development teamÆs processes to determine which combination of infrastructure options, operating performance and operating rules best achieve project goals. All systems can be divided into a series of subprocesses. Conventional management and design practices focus on the optimisation of these system components. However, the interaction between subprocesses means that improvements made to the individual components do not necessarily translate into total system performance improvement.TSG Consulting advocates a ætotal integrated system approachÆ to understanding the behaviour and performance of complex interacting systems. In a constraint-based integrated set of processes, the instantaneous system capacity is limited by the subsystem component capacity that is the bottleneck at that point in time. Additionally, real world stochastic and dynamic influences tend to have knock-on effects across subsystem boundaries. This necessitates the requirement for simulation modelling to develop and validate solutions that are sufficiently robust to deliver sustainable outcomes. The key to maximising production is to understand the causes and effects the inherent variability has on component performance, subprocess performance and most importantly, the total integrated system performance. The correct use of simulation modelling techniques allows study teams to evaluate the relative merits of different capacity enhancement proposals. Put simply, when done well, simulation modelling provides a quantitative and rational process to enhance the knowledge and insight needed to make informed decisions.

Jan 1, 2007

By Haartti J

Generally when equipment is chosen for solving a dewatering problem, the equipment is based on one of following physical methods: gravity (sedimentation, screens), vacuum (vacuum drum and disc filters, belt filters), pressure (filter presses, hyperbaric filters) and centrifugal forces (centrifuges). The choice of method and type of equipment depends, among other things, on the requirements on the maximum water content allowed in the filter cake and on the particle size distribution and the concentration of solids in the material to be dewatered. All the above-mentioned equipment has its benefits and drawbacks. The conventional vacuum filters of drum or disc type are of a simple construction with few parts to be replaced, but these filters produce a filter cake with a fairly high moisture content, and a dryer is required for additional drying. In most cases the use of pressure makes it possible to produce filter cakes with the desired moisture content but the equipment is of complicated construction, leading to high maintenance costs . In addition to this the consumption of compressed air is high. The capillary filtration to be described in this article is a dewatering method which combines the benefits of both the conventional vacuum disc filter and the filter press. The capillary filter produces low cake moistures with a machine of very simple construction similar to that of the vacuum disc filter.

Jan 1, 1993

By B R. Olsson, N Marinopoulos

To establish the design and the capacity of the Stanwell Magnesium Plant, Australian Magnesium Corporation Ltd (AMC) with Fluor Australia has modelled the operation of the magnesium plant using ARENA Simulation Modelling. The reliability model has been used to evaluate: surge capacities required between different sections of the plant; critical equipment requiring standby capacity; the number of trains required for different sections of the plant; and potential capital cost reduction options. The reliability model was established using the detailed Process Flow Diagrams, reliability information from literature and maintenance, operation and start-up experience from the Demonstration Plant. The model was run with different plant configurations to assist AMC in determining the most effective configuration to provide the production capacity at the lowest capital cost. The model was not only able to confirm the plant capacity to the independent technical expert but was able to minimise quantitative risk by minimising the quantities of hazardous materials on site. Fluor Australia provided the ARENA simulation expertise and has used this software for optimising new plant design and to establish improvements in operating plants. Reliability modelling is a normal feature of chemical plant design but is rarely used in the resource industry. The experience gained by AMC in the modelling system has indicated that metallurgical plant design can be improved by the application of reliability modelling.

Jan 1, 2002

By T Raynlyn, J J. Campbell, J M. Young

In order to correctly predict the performance of beneficiation processes, such as hydrocycloning or ultrasonic treatment of iron ore fines, it is important to understand possible changes in size distribution, mineral composition and textural peculiarities. During beneficiation processes, iron ore can be subjected to various physical actions which may result in changes in size distribution. In the case of soft or friable ores, attritioning and/or deagglomeration may have a significant effect on both separation performance and product stream specifications. Optical image analysis tools, which give statistical information on a particle by particle basis, can help in better understanding the response of the ores to these processes. An experimental study has been conducted to investigate the response of a haematitic-goethitic iron ore to a combination of stirring and ultrasonic treatment. The effect of stirring and ultrasonic treatment on the size and mineral distribution has been quantified using image analysis and automatic ore texture classification. This approach has been applied to several size coarse fractions of the initial feed and product. The results show that, following treatment, the mass proportion of ore texture classes which contained higher amounts of ochreous goethite and kaolinite had significantly decreased compared with that in the feed, while the proportion of texture classes where haematite was the major mineral had increased. Liberation analysis also showed a significant increase in the proportion of particles with more than 95 per cent haematite and vitreous goethite.

Jan 1, 2007

Although the bromo-cyanide or Diehl process for the extraction of gold from its ores is used on several of the Kalgoorlie mines, very little information has been published on the original process, and no details are available from the various mines now using it. The following description of the process as carried on at the Hannan's Star plant, where several modifications were introduced by the author, will therefore be of interest to mining men, and it is hoped that some discussion on this paper will provide further useful information to the mining community.The process was first installed on the Hannan's Star mine, where a full working plant was erected by the London-Hamburg Co. In their contract they guaranteed a 91 per cent. extraction on a sulphide ore of 15 dwt value. This was considered a very high extraction at the time, and the plant successfully carried out its work.The new features in the process were the finer grinding of the ore, for which purpose the tube mill was introduced, and the addition of a solution of bromo-cyanide to the vats under ordinary cyanide treatment, whereby a higher extraction was obtained in a shorter time. The main difficulty in the process was the easy manufacture of the bromo-cyanide solution, but this was eventually overcome. The mixed salts now supplied by the LondonHamburg Co. are in every way satisfactory, and are supplied at such a price that the process compares favourably with any other from a cost point of view.

Jan 1, 1907

In the early 1950's, it was forecast that there would be, worldwide, a need for approximately sixty computers! Included in that estimate was provision for a considerable amount of geoscience modelling. Since 1950, the role and concept of the computer has changed. With that change has come alteration and adaptation within industry in order to better utilise the services and tools that computers can provide. For example the science of statistics prior to the computer was regarded as an intractible speciality. Computers have allowed the exploitation and further generation of statistical theory. In turn, as the science of statistics has become practical and relevant, the mineral geologist has moved from being essentially "a-numeric" to "non-numeric" to highly skilled in the application and use of very sophisticated statistical concepts. The modern computer provides the opportunity to perform many of the old practices more conveniently and/or economically and, perhaps more importantly, for exploration it provides- an enormous range of activities which previously would have been impossible. Such new activities allow for imaginative and creative application and extension of basic theory into practical situations, which when used by well trained, able people can open up new avenues of exploration. However, the use of such tools by poorly trained or incompetent people can lead to errors potentially as great as any success derived from the same tools. This paper reviews some applications of the computer to exploration, and attempts to discuss likely future developments.

Jan 1, 1987

By Hegedus M

The Hydrogeological Survay of the bauxite mines in Hungary was establisned 30 years ago. The goal of the HS has been to collect the all available date needed to solve the hydrogeological problems of bauxite mines. The results of activity of the HS have been summarized in the annual reports-. This report is going to present a few methods to evaluate the hydrogeological properties of fissured, karstic rock ie. the evaluation of drilling mud losses, the statistics of core samples evaluated by a special computer program for calculation the porosity and permeability of the rocks. An experimental injection test is presented together with the development of a new portable instrument to get signes of the water table change during the injection test in every two second. It can be proved that the flow around the well may be a transient one if the yield of the injection exceeds a definite one (Figure 2.). It was observed that the permeability calculated from the pumping test date may be 1.2-1.6 time higher than it coming from the injection test. A practical example is presented also how to use the results of the HS for designing the dewatering of a new mine together with an analogous computer model to forecast the yield expectable for making the drift tunnel. A suggestion based on the hydrogeological feature has been done for the dewatering without using electric energy (see Figure 3.-6.).

Jan 1, 1988

Scientific drilling and blasting techniques are currently being presented to the mining industry as an aid in the overall optimisation process. The degree of success in the development of these techniques over the last ten years has prompted statements that generally relate to blasting becoming a science rather than an art. Many of the techniques are currently operated or at least analysed by scientists. As such, their use has been restricted to project type activities while the more routine activities associated with day to day mining has continued to be carried out by engineering rather than scientific staff. Some of the scientific techniques will remain legitimately as a project or an occasional use facility. Generally speaking a cost/benefit analysis at a particular mine will decide the level of use. This should logically highlight a number of techniques with potential of regular mine site use. Regular mine site use implies mine site analysis and hence the gulf between the scientist and mine operator/engineer must be addressed. There are all sorts of solutions and they are not mutually exclusive. One alternative could be to increase specialisation at the mines. With "career paths" becoming more formalised the trend would seem to be away from mine site specialists unless, for instance, this specialisation was provided by term secondment from research establishments. Another alternative could be the scientists themselves applying their developmental skills to "humanise" and "package" the projects in such a manner that they can be routinely used at mines.

Jan 1, 1990

By M McCarthy

Attraction, recruitment and retention of quality mining engineers is becoming increasingly difficult for many mining companies. Part of the problem is attracting young professionals, especially given the decline in graduating engineer numbers, and the other is balancing the new engineerÆs development with business needs. The evolution of the graduate program at Olympic Dam over the last five years has resulted in substantial benefits for both the engineer and the company. The program has developed to provide structured exposure to key areas of the mine enabling new engineers to step into vacated roles as the need arises. The pool of quality engineers generated by the graduate program is a buffer against high industry turnover and helps reduce future recruitment expenditure. Olympic DamÆs program goes beyond conventional recruitment of graduate engineers. Innovations designed to improve intake include the employment of graduate engineers as well as final year students, retraining of existing personnel from other backgrounds and fast track recruitment for previous vacation students. By employing a cross-section of professionals to complement the generic university graduate, the company takes full advantage of the relevant lifestyle experience belonging to the individual, which is a substantial factor in turnover. Study assistance and a salary paid for final year students and mature age students often creates a loyalty that lasts beyond graduation. Careful selection of vacation students increases the ease of recruitment at a later stage and ensures that full advantage is taken of the relationship developed previously between the company and young professional. The evolution of recruitment at Olympic Dam has seen a decline in the turnover statistics of young mining professionals.

Jan 1, 2005

Agitation leaching data has generally not been analysed to extract the maximum amount of information that is available. Analysis of heap leaching systems has been developing over the last five years to include the underlying rate determining process. This has been found to be diffusion control for all copper leaching; irrespective of whether they are oxide or sulfide minerals. Extension of the diffusion model has enabled better scale-up protocols to be developed. Acid consumption in copper heap leaching operations has been found to be a first-order chemical controlled system. The analysis of the data is relatively straightforward. However the interpretation and scale-up is not as direct as for agitation leaching. The differences in the residence time distributions (RTDs) are required to properly account for the scale-up between test columns and field. The leaching of oxide copper in agitated systems has also been found to be diffusion controlled. However, there are significant differences in the control mechanisms. Initially the leaching control is the supply of acid to the mineral surface. This is limited by the diffusion through the surface boundary layer and is thus subject to the level of agitation. Higher agitation provides thinner boundary layers and faster diffusion rates. Similarly, higher grade material creates a thicker concentration boundary layer and relatively slower leaching. Acid consumption in agitated leach systems is also a first-order system. However, the interpretation of the RTD is easier from batch testing to continuous multiple CSTR series plant operations. Altering the method of acid delivery can significantly reduce acid consumption rates. Predilution of the acid minimises the local acid concentration near the addition point and can reduce the consumption by up to 50 per cent. Modelling of the combined leach rate(s) and acid consumption rates in agitated systems allows comparison of various leaching strategies and selection of the most appropriate. Similarly, the model allows the identification of economic limits to leach recovery; where the cost of acid consumption is greater than the value of the copper recovered. From this analysis selection of residence times for agitation leaching can be determined. The modelling tools are useful in identifying optimum conditions for the leaching process.

Jan 1, 2005

The development of reliable and accurate solution sampling systems plus on-line atomic absorption spectrophotometers and voltammetric analysers at Pasminco Metals - EZ's (PMEZ) zinc refinery at Hobart, Tasmania, has led to extensive implementation of On-Stream Analysis (OSA) throughout the hydrometallurgical circuit. These systems complement industrial autotitrator and colorimetric analysers and with the comprehensive use of a powerful integrated Distributed Control System (DCS), provide extensive monitoring and control of all the important in solution' parameters for the plant. Samples can be left unaltered, or filtered or settled, to remove solids. They are then precision diluted and pneumatically transported to analyser shelters, where they are analysed for zinc, acid, copper, cadmium, lead, antimony, cobalt, nickel, mercury and ferrous, ferric and/or total iron. The range of analyses depends on the sample itself. The results are used for feed forward and/or feedback control of reagents where possible, or simple trend monitoring and out-of-specification alarming when closed loop control is not practical. The overall system reliability and accuracy is such that many daily composite plant samples are no longer analysed off-line. Operator sampling has also been reduced, and in two places, autotitrators with automatic sample pre-treatment have been installed for preparing and analysing samples collected by operators.

Jan 1, 1993

Urban railway systems need high invest- ments, especially if their routes and stations have to be placed in the subsurface. In the FRG the construction and equipment cost of urban underground railway systems are in the range of 60 to 100 Mill DM per km tunnel. For this reason, track sections on the surface and on elevated structures are used as far as that is possible. Considering whole systems, the costs are in a range from to 45 Mill DM per km length for a metro system with about 80 % of its tracks and stations in tunnels and from 20 to 25 Mill DM per km for a light railway system with about 25 % subsurface infra= structure. The amount of route lengths in tunnels depends on the size of a city, the situation regarding above ground structure and free space on the surface, the level of service quality which has to be achieved with the railway system etc. Despite of the urgent needs to improve the transport conditions there very often arise doubts if an urban railway system is really necessary and can be justified in an economic sense. The experience from many cities around the world shows, that there arise a lot of benefits from urban railway systems, especially with larger sections placed under- ground. They are to be found in the interests of the operator (f.e. operating costs), the user (travel time, quality of service etc.) and regarding social aspects (environmental protection, accidents, consumption of energy Etc.).

Jan 1, 1987

The society in which we live is one of change, and we professionals are part of that society. The importance of this simple and obvious statement is often overlooked. My Presidential Address examines the question: can professionalism survive in our changing society?There is ample evidence to show that our society is changing, and that the rate of change is exponential. This rapid and accelerating rate of change is what Alvin Tomer refers to as "future shock". Rapid change means that we do not have time to become accustomed to what is happening around us and to feel comfortable with it; the greater the rate of change the greater the discomfort. The effect that this has on people is varied; the change may be either expected or totally unexpected.The rate and extent of change in society is not the same for all countries nor for all industries or occupations. Change is more rapid in Japan, Korea or Taiwan, than in Australia. It is more rapid in our cities than in the bush, more rapid for professional businessmen than for farmers. In our minerals and petroleum industries, we are still adjusting to the great changes that have taken place over the last fifteen years. In the past, products from our industries were sold on a free and open market. Today, mineral development and production in most undeveloped countries and some developed countries is manipulated for political, social and economic reasons. Changes of this nature have had a devastating effect on the operations of established mineral producers in the democracies.Because of the accelerating nature of change, we must recognise that the past is not a reliable guide to the future.Although extrapolation of the past into the future is a basic ingredient of commercial survival, extrapolation is less and less reliable.I borrow from others in quoting the Irish proverb: "The future is not what it was".The future is where our business lies and most of us at this Conference must endeavour to understand it and adjust to it. I believe in the old adage that:You can't know where you're going if you don't know where you've been and where you are at.There are a number of major factors which have created change within our social, economic, and industrial environment in recent years.

Jan 1, 1985

Although laterite ores already provide a significant proportion of the world's nickel and cobalt production it is anticipated that they will surpass sulphide ores as a source of nickel in the next century. The most recent period of greenfield nickel project construction was during the 1970s when it was notable that all of the eight new plants were based on treating laterite ores. This was because of the relatively large selection of available high grade laterite ore deposits amenable to cheap open cast mining and a paucity of high grade sulphide ore prospect alternatives. Of the three processing options for treating laterite ores: 1. smelting for the lower horizon saprolite ore, 2. ammonia; and 3. acid leach for the upper horizon limonite ore, smelting currently accounts for about 80 per cent of nickel production. In the future, as saprolite ore grades decline because of relatively high exploitation rates, the incentive to process the large untapped reserves of limonite ore will increase. The high cobalt content of limonite ore also makes it ideally suited to processing by a hydrometallurgical rather than smelting route. With only two exceptions, all saprolite smelting operations have a Class 2 nickel end product (largely ferronickel) and do not produce a cobalt by-product. As a result of technological advances, the modified ammonia leach process for limonite and transition ore as undertaken at Yabulu, now allows the production of pure nickel metal as a Class 1 product, along with significant tonnages of cobalt by-product. The mixed Ni-Co sulphide intermediate product of the pressure acid leach processing of limonite ore at Mon is converted to Class 1 nickel and cobalt metal at Fort Saskatchewan, Canada.

Jan 1, 1996

The papers in this section of the conference and indeed the conference as a whole will rightly focus on the recent û the state of play around the Pacific Rim. However, to set the scene I propose to take a longer-term perspective. In so doing I wish to illustrate and emphasise that change is normal and natural û to paraphrase Bob DylanÆs 1963 classic, æThe times they are (always) a-changinÆ Æ. The challenge is how to cope with such change, in an industry, a corporate and a personal sense. A further challenge for geologists, both exploration and mine-based, and indeed for anyone, is to understand where they fit in the broader picture. For several reasons it is appropriate first to look briefly at the minerals industry in the Pacific Rim around a century ago. It was here in Adelaide in April 1893 that the first general meeting of the Australasian Institute of Mining Engineers (or The Australasian Institute of Mining and Metallurgy as it later became) took place and where the Centenary Meeting was held in 1993. The late 1800s and early 1900s was a period of extraordinary change in the minerals industry regionally and worldwide. The industry benefited from the economies of scale provided by improved mechanisation. It further benefited from the introduction of technically qualified professionals, such as chemists, metallurgists and mining engineers, although the usefulness of geologists had yet to be recognised commercially. With the rise of such professionals, technical societies formed and flourished. At the same time international financial markets and trade were expanding, a gold standard was widely supported and the financing of mining ventures was well established. Mining was an international business and its people travelled widely. As a consequence of the better-educated mining professional, the ready exchange of knowledge and the availability of finance, new processing techniques such as pyritic smelting, the cyanide process and flotation were developed. These, together with much improved materials handling in the mining and processing phases, dramatically changed the economics of the minerals industry.

Jan 1, 2004

By S Brochot

In cases where coarse gold is present in a deposit, it is usual to use the screen fire assay (SFA) method to analyse the samples. There is no doubt that this method is more accurate than the standard fire assay (FA) and reduces the risk to have a systematic bias. Nevertheless, the difference between the analytical errors of both methods can be glossed over when the overall sampling error is added to obtain the measurement error. In that case, the advantage of the SFA cannot justify its higher cost.The current paper attempts to address this question in the case of a gold ore deposit with visible coarse gold in various sampling situations (drill core sampling in exploration, blasthole or chip sampling in mining exploitation). The overall measurement error is estimated taking into account the analytical error and all the sampling error components following the Pierre GyÆs theory of sampling.Firstly, only the last sampling stage is considered when the pulverised sample is processed either to obtain one analysis sample for a FA or to be screened and subsampled for a SFA. The calculated measurement error clearly shows the advantage of the SFA specifically in presence of coarse gold. Secondly, the half core sampling is studied to explain the observed discrepancies when controlling the second half core. Finally, the blasthole sampling is treated using in situ heterogeneity models to show that the relative advantage of the SFA is hidden by the large overall sampling error.In conclusion, the choice of the assaying method is discussed at the light of the overall measurement error and in accordance to the analysis objective.CITATION:Brochot, S, 2012. Standard fire assay or screen fire assay? Application of the overall measurement error approach to choose the most appropriate method, in Proceedings Sampling 2012 , pp 135-142 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By B N. Morrison

In all metallurgical plants metallurgists require analyses of the various intermediate products, eg flotation feeds, flotation concentrates, tailings, mattes, slags, etc to monitor the efficiency of the plant processes and for plant control purposes. Traditionally these samples have gone to off-site laboratories and there can be some considerable delay before analytical data are received. On-line monitors have to be used for plant control purposes and these are difficult to maintain and can give poor quality data. Recent technological advances in automation in analytical laboratories now allow a far quicker turn-around time for analytical data so they can be of more use to the metallurgist. Automation, which involves the use of robots and fewer people in laboratories, has the added benefit of providing higher quality data as the possibility of human error and bias is minimised. Differences between conventional manual laboratories and automated laboratories are described. Automated analytical laboratories are now becoming the laboratories of choice for mining companies which require large numbers of samples to be analysed on a 24/7 basis on similar sample types using the same sample preparation methods and analytical procedures. Automated laboratories have now been installed in platinum, iron ore, copper and aluminium producing mining companies. A further advantage to metallurgical plants is now the possibility of siting automated analytical laboratories in-plant and designing the plant around the laboratory. Concentrator streams, slags, etc can be sampled by automated samplers, the samples transferred by automation to the in-plant laboratories and all sample preparation and analyses carried out by automated processes. These laboratories require a minimum of staff. Such automated in-plant laboratories have been installed on a platinum mine flotation plant, a platinum mine smelter and steel plants. One is in process of being installed on an iron-ore mine with the sampling being carried out by an automated sampling tower. The procedures followed in planning an automated analytical laboratory for a metallurgical plant are described in detail in the paper. The platinum plant smelter automated system which includes rapid transport of samples by air-tube to the laboratory for the analysis of the samples by XRFS is also described in the paper. It is concluded that automated analytical laboratories can be retro-fitted to most metallurgical plants but they are best suited to greenfield sites.

Jan 1, 2008

By S Kodate, Ö Aydan, Y Suda, J Tomiyama

Fracture zones are commonly found in the Earth’s crust. These zones may cause very severe engineering problems. Therefore, the formation and the assessment of the mechanical characteristics of these zones is of great concern for rock engineers. A new double shearing jig was used to study the formation of shear zones in rock under static and impact loading conditions using the device developed by the authors. A series of experiments were undertaken to investigate formation on the formation and characteristics of fracture zones in laboratory. Although actual fracture zones are more complicated, various tests give some insight view of the formation of fracture zones as well as some information on their mechanical behaviour under both dynamic conditions and static conditions. The authors report the outcomes of these experiments and discuss their implications in practice.

Nov 29, 2022

Industry has a very special request to make. Environmental issues must not be allowed to become a factor of competition so that nations or individual industries can gain economic advantages for themselves by encroaching unduly upon the environment. An international harmonisation of the demands imposed on specific industries and industrial plants where discharges are concerned is therefore essential. The same applies to any to any action contemplated against noxious products. An important step towards that goal is no doubt represented by the United Nations Conference on the Environment scheduled for 1972. Conclusions: Australia must recognise its responsibilities in an inter- national movement to control pollution. It must react on a national scale to a problem which is threatening our whole national environment. To gather, collate and coordinate the information needed to ensure policies which strike a balance between conservation and development, we must look towards the Commonwealth to coordinate the activities of its own instrumentalities and those State and independent bodies working in the area. Financial aid must be provided to stimulate research and later to ensure that environmental protection policies are observed. These policies will be founded on social economic theories which will be both practical and sound, The United Nations conference on the Environment is scheduled for 1972 and in this is the opportunity for international cooperation. Cooperation in the field of controlling legislation and the collection of much needed data. There is an imperative need to assemble facts for world use - an international know-how bank which acquires the most sophisticated technology of process design and waste purification. Arising out of this Conference, is it too much to expect that there could be established an international authority for environmental control, whose activities are governed on a multi-national basis? Such an organisation would have as its primary concern the collection and classification of official regulations, as well as the sheer collation of data to permit economic evaluation of the costs of conservation of the environment. There is an international scope with different factors involved, including industrial technology: in other words, the concrete measures taken against industrial pollutants ought to be more or less identical for similar industries irrespectives of the countries in which they operate. The assembling of an international common foundation of knowledge is imperative so as to acquire the most sophisticated technology of process design and waste purification available for all who are interested.

Jan 1, 1971