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By Marvin Barnes

The Sacaton mine is a relatively new open¬pit copper mine owned by Asarco, Inc., which has been in production only a few years. The mineral deposits consist of two ore zones; a western, near-surface zone minable by open-pit methods, and a deeper eastern zone which will have to be mined underground, probably by block caving. The copper deposits are related to small quartz monzonite intrusives implaced into Precambrian granites. Both rock types act as hosts for the copper mineralization, which has been secondarily enriched sufficiently to constitute ore. In the western zone the enriched supergene chalcocite has been subjected to postenrichment oxidation processes with partial destruction of the chalcocite blanket. The deeper eastern chalcocite zone has not been as severely affected by later supergene processes. Several mineralogical populations are represented in the total copper deposit. Leached capping overlies the chalcocite enriched zone, and in the western ore body there is a very irregular interface between the leached and enriched zone, which is complicated by oxide copper minerals irregularly distributed. Primary lower-grade chalcopyrite mineralization occurs below the enriched zone. When mining commenced near the top of the enriched zone, considerable difficulty was encountered in correlating the actual grade of ore in place with the estimated grade of the mining blocks. The mineralogical complexity and fairly wide spacing of diamond drilling made reliable grade estimation of individual ore blocks a difficult procedure.

Jan 1, 1979

By Neil B. Prenn

Drill-hole contamination has been a problem for many years. Contamination of rotary drilling has been well documented. More recently contamination in wet reverse circulation drilling has been noted by Echo Bay and others at the 1991 AIME annual meeting. Mine Development Associates (MDA) has worked on a number of projects at which contamination of drill-hole samples has occurred. Properties are commonly acquired with drilling accomplished by other companies and at times the only records of the drilling program are the drill-hole logs and assays themselves. Identification of contaminated zones is sometimes difficult to determine. Most geologists and engineers in the industry are aware of the magnitude of the problem, as contamination is a relatively common problem with wet reverse circulation drilling. MDA has developed a computer program to help determine if contamination has occurred when using reverse circulation drilling, based on cumulative distribution curves and by a process we call decay analysis. Most deposits are not homogeneous throughout the deposit, but exhibit a characteristic drop-off or decay of assay values around higher-grade drill-hole intercepts. Using graphs of this characteristic decay and cumulative frequency distribution, we can use the program to help determine contamination in several ways. This paper will discuss the use of decay analysis at three gold deposits where contamination is known to have occurred. In one of the deposits decay analysis was used, successfully to determine if contamination had occurred, while in the other two the decay analysis was used to verify our decay analysis procedure.

Jan 1, 1992

By R. L. Grayson

The Office for Mine Safety and Health Research, National Institute for Occupational Safety and Health is responsible for providing research leadership in the prevention of mining work-related illness, injury and death. Planning of the NIOSH FY99 research program focused on the comprehensive collection and risk analysis of fatality, injury and illness data according to commodity and mine type. This data, coupled with the mapping of information obtained from stakeholder meetings over several years, provided the basis for prioritizing research needs. Results of the combined analysis were compared to the FY98 program to identify surveillance and research gap areas. The FY98 research program was then assessed according to commodity and mine type and compared with exposure assessments, traumatic fatality rates, injury rates and employment trends in each commodity-mine type combination to gain insight into the potential balance of the future research program. This paper presents the methods, data and results of this planning process.

Jan 1, 2002

By C. Einberger

Groundwater Monitoring is typically required by regulatory agencies at potentially hazardous landfills or surface impoundments. Agencies have often required an arbitrary number of wells with limited evaluation of the effectiveness of the network to detect a leak. A Monitoring Efficiency Model (MEMO) has been developed to improve the design and cost effectiveness of monitoring well networks. MEMO 15 an analytical model that simulates the migration of hypothetical contaminant plumes from a site and quantifies the efficiency of alternative well network designs in detecting the plumes. The computed monitoring efficiency provides a quantitative measure of the well network adequacy based on hydrogeologic considerations. The model was recently used to design the groundwater monitoring well network for a heap leach pad at the proposed Beartrack Project.

Jan 1, 1993

By R. V. Ramani, S. Skankar

Available literature on the effect of re-entrainment on overall airborne dust concentration in mine airways or the fundamental mechanisms of coal dust re-entrainment in mine atmosphere is scant (Shankar and Ramani, 1991). Therefore, as part of the Respirable Dust Center's ongoing research, the following three-part study was undertaken: •a study of the re-entrainment phenomena of anthracite and bituminous coal dust particles in a wind tunnel under the influence of varying air velocities; •a study of the same in the Lake Lynn Laboratory Mine of the USBM with both air flow and walking by personnel causing re-entrainment; and •the mathematical modeling and computer simulation of the re-entrainment phenomenon. In this paper, results from the re-entrainment studies in the wind tunnel and the Lake Lynn Laboratory mine are presented. Comparing the results from the two studies, it was observed that increasing the air velocity increased the rate of re-entrainment (Shankar and Ramani, 1994a) and the rate of re-entrainment decreased with the time of exposure of the source dust to the flowing air. In addition, when the source dust was composed of particles of different sizes, the airborne dust concentrations due to re-entrainment were higher than when the source dust was composed of particles of the same size. The contribution of airborne dust concentration due to airflow was negligible compared to the contribution due to walking.

Jan 1, 1996

By Anthony G. Fonseca, W. W. Wen

About 45-50% of the coal mined in the U.S. passes through coal preparation plants; east of the Mississippi River this number increases to about 75-80%. Although the cost for coal preparation is worthwhile to some, the coal industry faces the challenges of continuing downward pressure on the price of coal and the impact of new environmental regulations. Coal preparation, as commercially practiced today, is an effective process achieving 75-803 ash reduction, 15-8m trace element reduction, and 85-90% Btu recovery; it is less effective for pyrite reduction (35-70%), and on-line operating time (40-60%), and suffers from obsolete control systems. Methods will be discussed for reducing costs of coal preparation and improving the performance of coal preparation plants. Comments are included on equipment selection, especially for -28 mesh coal, and prep plant operation and control practices. Btu recovery, ash and pyrite reduction, fines processing including dewatering and slurry fuel use options are emphasized. Trace element removal and expert control systems for maximization of prep plant operation also will be highlighted.

Jan 1, 1995

By R. V. Ramani, W. Miola

The MSHA prescribed method for the determination of quartz in airborne respirable-dust samples from underground coal mines is the P-7 method, a combination of low-temperature, radio-frequency ashing (LTA) and infrared analysis (IR). There is no prescribed procedure for quartz analysis in bulk samples of coal and host rock. Dispersive infrared (IR), Fourier-transform infrared (FTIR) and X-ray diffraction (XRD) methods are most commonly used for the analysis of quartz in powders. Several aspects of the experimental procedures, such as the preparation of the analysis sample from bulk samples, ashing techniques, scanning procedures, peak measurement location, calibration techniques, sample amounts, size consist and data interpretation, affect the results from each of the methods differently. Significant differences in analytical results obtained from X-ray diffraction (XRD) and infrared spectroscopy (IR) on the same samples are reported. All studies point to the need for reliable quartz analysis methods. In a recent research program, a procedure for preparing bulk-coal and host-rock samples for quantitative quartz analysis was developed. Further, the results from X-ray diffractometry and infrared spectroscopy for quartz content on identical samples were compared. Calibrations with pure and mixed standards were used to assess the influence of particle-size distribution, matrix and calibration on the analytical results. In this paper, several issues concerning the measurement of quartz in the samples of coal, host-rock and airborne respirable dust from mines are outlined and quantified.

Jan 1, 1996

By E. T. Sugar

English China Clays, the world's largest producer of China Clay, has its main production capacity in the South-West of England, where a complex of pits, refining plants, dryers and ports covers an area of approximately 100 square kilometres. The possibility of a computerised information network was first considered in 1980. The system was required to provide information at the central level and also at local plant level to improve co-ordination and control. Immediate access by any authorised user, and flexibility of interrogation were important aims. A small micro-based prototype system was implemented in 1981, and later that year development of the mainframe system commenced. This latter system will provide at least one terminal in every works location and will allow inter-communication of laboratory test data as well as detailed stock levels and production data. An integrated system for order processing will allow stock levels to be monitored in relation to anticipated requirements. The system has been developed by the Data Processing Department using the IDMS database package running on an ICL ME29 mainframe. It was decided to use microcomputers as terminals, which although more complicated because of protocol emulation allows stand-alone applications to be run on the same equipment. Those applications concerning Production Planning are outlined in the paper. Communication on the network is by synchronous transmission over dedicated lines. All data is stored on the central database with terminals accessing it in a star configuration. The system is currently partially implemented with 30 available screens at 18 separate worksites.

Jan 1, 1986

By L. R. Stoiser

The mineral resource potential of the Los Bronces deposit was successfully evaluated by an intense, coordinated field program over a 37-month period (April 1978 - May 1981). This project was part of a much larger study to determine the economic feasibility of expanding the open-pit, mine-mill operation 10-fold to 80 kt/d (88,000 stpd). The resource project included more than 120 km (74 miles) of core drilling and 64 km (40 miles) of drill rig access way construction under adverse topographic and climatic conditions, detailed geological mapping, and other related activities. The Los Bronces deposit is composed of an earlier mineralized porphyry-type body intruded in part by a large complex of mineralized hydrothermal breccia pipes. The mineralization is hosted by intrusive and extrusive igneous rocks. Various stages of erosion, oxidation, leaching, and supergene enrichment of copper are present. Drill hole indicated geologic reserves are estimated at 1.3 Gt (1.4 billion st), averaging 0.81% copper and 0.016% molybdenum at a cutoff grade of 0.6% copper equivalence decreasing to 0.25% over the life of the mine. Trace amounts of silver are also present.

Jan 1, 1987

Those who have had an occasion to apply geostatistics to the estimation of ore reserves are familiar with the conventional approaches of estimating average grade of quality values for arrays of regular grid squares or blocks. Further, the technology to perform geostatistical analysis and prediction for irregular two-dimensional areas has been available in a practical, readily useable form for some time. However, the generalization of this technology into three dimensions has been hampered by lack of a suitable geometrical characterization for realistic, three dimensional shapes and volumes. The extension of these estimation techniques into three dimensions has now been made possible by a successful integration of the volume modelling capabilities of 3D Component Modelling with proven 3D Geostatistical Techniques. The result is a powerful new technique for mineral ore reserves estimation in a practical, useable form. The technique allows direct geostatistical estimation of grade and quality values for precisely defined, irregular, realistic, geological, and mining shapes or volumes. This paper describes the two technologies, their integration and their application in practice to the estimation of mineral ore reserves. The paper closes with a discussion of the benefits provided by the new approach, in terms of accuracy, efficiency and practicality.

Jan 1, 1991

By J. F. Archibald

It is often alleged by mine ventilation engineers that no reliable method exists to forecast the levels of radiation to be encountered in future uranium mines. It results that the design of uranium mine ventilation systems is based on factors other than radiological hazards, such as radon and radon daughter concentrations, for which permissible limits are set. Ventilation has been used to date as the main control mechanism for radon and radon daughters. Although it has become increasingly difficult to provide enough ventilating air to reduce the radon gas and its daughter products to safe levels in some mining arrangements, it is not the object of this paper to discuss alternatives to ventilation. This paper will describe a methodology followed by the authors over the years to estimate the levels of radiation to be encountered in underground and open pit uranium mines. Ventilating air is used to maintain working level concentrations within safe limits. The sources of radon and radon daughters and the quantities of each which will be produced, will be of great value in planning and designing a ventilation system to control them. This information can afterwards be integrated into the overall mine design. The methodology to be outlined can also be used to estimate, given a mine design format, the radiation levels to be encountered. If levels are not acceptable, modifications in the mine design can be made at an early stage. The emphasis is placed on an integrated effort where the ventilation engineers and the mine design engineers work in close collaboration from the very start of the mining project. Estimation of radon and radon daughter levels can be initiated as soon as core samples are obtained from the exploration programmes.

Jan 1, 1980

By Eivind Grøv

"INTRODUCTION Tunneling and underground excavation is related to handling of uncertainties, risks associated with geological conditions are significant and ‘unexpected geological conditions’ often claimed. This fact was brought to the table long ago, and ITA (the International Tunnelling and Underground Space Association) published its 25 Recommendations on Contractual Sharing of Risks in 1988 (Ref. 1). This public-cation constitutes an important asset to the tunneling industry in terms of being a guideline for those working with contractual issues, even today almost 30 years after being published. A more recent document is the ITIG code of practice for risk management of tunnel works from 2015 (Ref. 9). Various countries or geographical regions have their own view and tradition on risk sharing and tunnel contracts. In Scandinavia unit rates contracts are most commonly used with bid-build model, it shares risk between owner and contractor, owner retains the risk for geological conditions while contractor carries risk for performance efficiency. Rock strengthening is determined assessing rock mass quality encountered at tunnel face. Grouting is applied to stem water. Actual quantities may differ from the contract’s BoQ but a flexible contract with remuneration is installed to enable adjustment of actual quantities. Variations of quantities involve a clause to adjust construction time. Unit price contracts deals with expected and foreseen still ‘unexpected geological conditions’, if the ‘unexpected’ element results in variations in quantities. Work activities have quantities and ‘standard capacities’ for regulation of construction time. Variations in quantities are expected in tunnelling and hardly deserve the term ‘unexpected’. If truly unforeseen geological features necessitate work not included in the BoQ, then the contract must be supplemented and can be said to be inappropriate. Fixed price contracts may not provide the intended predictable cost and is as such also inappropriate in the view of a risk sharing principle, once the geological baseline proves to be incorrect. ‘Adjustable fixed price’ contracts, combining unit rate and fixed price, may prove suitable."

Jan 1, 2016

By Donald W. Gentry

Mine valuation is a multifaceted, interdisciplinary process by which the economic viability of an old, existing, or new mining property or venture is determined. The problems associated with arriving at a representative and accurate value for a mining property are complex and numerous, and the procedures utilized in determining these values vary from simple, back-of-envelope calculations to sophisticated mathematical manipulations requiring computer modeling and analysis. Regardless of the complexity or the degree of sophistication associated with any particular project, the evaluation process must ultimately provide management with two basic types of information. First, the evaluation process should indicate whether or not the mining project is economically viable after careful consideration of all engineering, environmental, geologic, and other variables pertaining to the project. Second, the evaluation process should provide management in- formation on the relative attractiveness of the project when compared to other alternatives. In some cases, it may be extremely difficult to supply this information for a project directly. Nonetheless, the evaluation process should and must present all information necessary in a format which can be incorporated into the decision-making process as expeditiously as possible.

Jan 1, 1979

By Edwin A. Harre, John J. Mortvedt

Plants obtain nutrients from both air and soil. They absorb carbon dioxide mainly from the air, although some carbon dioxide may be dissolved in soil water which is absorbed by plant roots. Carbon dioxide, a gaseous form of carbon and oxygen, supplies the carbon which usually makes up 50% or more of plant structure. Growing plants use water more than any other biological substance. Plant nutrients dissolve in soil water and enter the plant via root absorption. Water is then given off into the air as the plant breathes or transpires. Water also supplies hydrogen and oxygen to plants. Plant roots absorb nutrient cations or anions by contact exchange with soil clay particles. Inorganic or mineral nutrients essential to plants are supplied through the soil. Inorganic or mineral composition of plants usually is less than 5% of their weight. In most crop-growing areas, much of this nutrition is inadequately supplied from soil reserves and must be provided by fertilizers. The role of the fertilizer industry is to provide economical, efficient, good quality fertilizers to improve or maintain soil productivity for optimum crop production. The essential plant nutrients other than carbon, hydrogen, and oxygen which often must be added to soils or plants are categorized as primary nutrients (nitrogen, phosphorus, and potassium), secondary nutrients (calcium, magnesium, and sulfur), and micronutrients (boron, chlorine, copper iron, manganese, molybdenum, and zinc). These classifications are based on quantity of nutrients utilized by plants and do not imply their function or degree of necessity. One point of major significance to the fertilizer industry is that not all fertilizer minerals contain the plant nutrients in a chemical form available to the plant. A product which may be considered a fertilizer mineral may require substantial processing or treatment before it becomes useful as a nutrient source or fertilizer.

Jan 1, 1994

By P. Bottomley, M. Matthews

Maintaining an acceptable thermal environment in South African gold mines becomes increasingly difficult as mining progresses to greater depths where higher virgin rock temperatures are encountered. Current environmental practice offsets the resulting high heat loads by installing large refrigeration plants. However, with the continued escalation of refrigeration costs, it has become necessary to examine other methods for economically combatting the underground heat load. The Chamber of Mines Research Organization has recently been pursuing a programme to devise methods of reducing the flow of heat into underground workings at source. Although there are several sources of heat (such as machinery, men, and explosives), the most significant is that from the rock mass surrounding the workings (Bluhm et al., 1986a). The main thrust of the work has therefore been directed at predicting and devising methods of reducing this heat source. A great deal of theoretical work has been carried out on the prediction of underground heat flow. From a review of this work (Bluhm et al., 1986b) it became apparent that there are two major aspects which require attention, namely algorithms for predicting the heat flow around the advancing stope face, and a correlation of the theoretical work with accurate empirical data. In order to remedy this situation, new theoretical models have been developed (von Glehn and Bluhm, 1986), and heat flow measurements have been made in both a conventional stope (Bluhm et al, 1986a) and in a backfilled stope (Matthews u., 1987). A number of methods for reducing rock heat flow are being examined. These include the insulation of intake airways (Bottomley, 1985 ), backfilling with waste material of the worked out areas, and alternative approaches to the design of mining layouts, the mining method, and the choice of cooling strategy. This paper highlights the heat load reductions that can be achieved by backfilling the worked-out areas and by adopting concentrated mining. The first part of this paper summarizes the results of the measurements obtained in the conventional and backfilled stopes. The theoretical models are then described and comparisons are made with the measured values.

Jan 1, 1987

Marble has been recognized as a valuable natural resource ever since ancient times. Due to its peculiar aesthetic and technical characteristics as well as the lithotype uniqueness, it has widely been appreciated over the past centuries. In present times its production and demand are enjoying an increasing trend, with comparatively high market prices. All this considered, marble can be included among these natural resources whose exploitation provided, and still provides, an important contribution to the growth of the economic system. Nevertheless, there is at least one more important reason that makes marble a valued resource. For ages, marble represented one of the most important raw materials for sculpture sand architectural masterpieces, which constitute part of the cultural heritage of mankind. With this in mind, the value of marble is strictly related to its extraordinary capability to preserve cultural heritage and therefore to convey civilization from past to future generations. In other words, the role of marble should be recognized as being of the utmost importance in order to attain an overall objective of ?cultural sustainability?, that is, the assurance of the inter-generational flow of the cultural heritage capital. To achieve this sustainability goal, the priorities should be to protect and preserve the world?s artistic and architectural historical heritage, which require restoration works. In this field, a very il task is entrusted to the extractive industry: this industry, in cooperation with historians, art experts and public authorities, is in charge of detecting and supplying historical stones for restoration purposes, taking into consideration that, in order to restore a monument in a correct way, the same lithotypes the monument was made from are needed. These marbles are often no longer in production, so that it becomes necessary to find the location of the original quarries, as only there is it possible to extract even the small quantities of stones that are needed. In this case, the stone, located in its geological context, could have such valued characteristics as to be considered an important public asset and consequently a resource to be preserved and protected even beyond the market conditions. This important task should be carried out by the public administration through a targeted intervention of territorial planning and monitoring, which could include the support for the specific extractive activity.

Jan 1, 2003

By Scott Horton

In no Confederation of Independent States (CIS) country does the mining sector play quite so commanding a role as in the mountainous Central Asian republic of Kyrgyzstan. Its president, Askar Akayev, says he would like to develop his country into "a Central Asian Switzerland." However, in Switzerland, the gold is largely under the street along Zurich's renowned Bahnhofstrasse. In Kyrgyzstan, though, the gold is still in the mountains. Accordingly, Kyrgyzstan's recent adoption of a comprehensive new mining law has attracted widespread attention. Akayev recently completed a tour of the United States. His visit drew large crowds from the business community at events staged in New York and Washington, DC. The success can be attributed as much to the attractiveness of Kyrgyzstan's min¬ing sector as to the personal charms of the nation's president. Led by a half-billion-dollar investment by Canada's uranium giant Cameco, the mining sector is leading Kyrgyzstan's economic revival. And Bishkek is beginning to show some of the same signs of a "boom town" that already mark its Kazak neighbor, Almaty. Mercedes and BMWs already outnumber the Volgas on Bishkek's major traffic arteries. After nearly two years of debates involving government advisors and a final round of deliberation in Parliament, Kyrgyzstan finally adopted its second mining law. This followed quickly in the wake of measures enacted in neighboring Kazakstan and proposed in Russia. Kyrgyzstan's new law replaces the 1992 law "On Mineral Resources." It was one of the first enactments of an independent Kyrgyzstan. The 1992 law made a major contribution to the introduction of free-market economics in the country by ending the state monopoly over mineral exploration and development. It also laid the groundwork for an independent mining industry. According to Kyrgyz government reports, Kyrgyzstan has about 270 commercially viable deposits of almost 40 types of mineral resources. These include oil, gas, coal, precious-, nonferrous-, ferrous-, rare- and basemetals. However, the nation's key draw is gold. Since enactment of the first law, the government has issued more than 100 licenses for geological prospecting for and development of established deposits of gold.

Jan 1, 1998

By L. F. Zeiler

In the past, health concerns in coal mines have primarily centered on those elements which have been essentially inherent to the mining environment. These would include respirable coal mine dust, respirable crystalline silica, excessive noise levels, and diesel exhaust particulates. Commercially-available chemical products are prevalent on mine property. These potentially toxic materials are chemical formulations that can degrease, clean, and lubricate metal parts, separate coal from rock in float/sink operations, and aid in roof consolidation, among other uses. As the general public has become more aware of the hazards of chemical exposures, miners have likewise become more concerned about working with an ever-expanding variety of chemical products on the job. Often, product or chemical specific hazard communication training is inadequate or ineffective, and miners do not know exactly what the ingredients are in the products they handle, or the health hazards involved with their use or misuse. Currently, the Mine Safety and Health Administration (MSHA), by law, enforces 1972 Threshold Limit Values (TLV). MSHA is making preparations to adopt new personal exposure limits for enforcement. The values given throughout the article are 1994 TLV's and are not enforcement standards, but are used for discussion purposes. They reflect the current scientific thinking regarding personal exposure to these chemical agents. An overview of these products is presented, and the potential health hazards associated with their use are discussed. Controls needed to prevent overexposures, such as proper handling procedures and personal protective equipment, are covered. Methods used to collect and identify contaminants are presented.

Jan 1, 1995

By Jiachen Wang, Nan Wang, Yang Li

The energy structure and consumption ratio in China determine the practical demand for the collaborative mining of coal and co-associated resources. The multi-layer mining of coal, uranium, coalbed methane, and oil and gas co-associated resources, represented by the Ordos Basin, Junggar Basin, and Tarim Basin, faces numerous challenges. Additionally, coal has been found to coexist with various mineral resources in 33 coal-bearing basins worldwide. The scientific issues related to the multi-layer development of coal related co-associated resources urgently need to be addressed. This paper discusses the unique challenges and potential solutions in the multi-layer development of coal-related co-associated resources. The challenges include large extraction space, high mining intensity, intense overburden movement, rapid surface subsidence, and severe overburden damage due to repeated mining disturbances. Proposed solutions include the establishment of a correlation mechanism between multi-layer mining and the carrying capacity of the overburden environment, analysis of the impact characteristics of multiple field couplings, and exploration of their superposition evolution laws. The paper also proposes the development of a comprehensive evaluation and prediction system for overburden environmental capacity loss, a global sensitivity analysis model for overburden environmental capacity, and an intelligent identification and early warning system based on multi-source information fusion. These solutions aim to achieve scientific and precise mining with minimal overburden environmental capacity loss. And the multi-layer development of coal-related co-associated resources is a complex task that requires a multidisciplinary approach and innovative solutions, and further research is needed to validate these strategies and explore new methods and technologies for efficient and sustainable extraction.

Jun 25, 2024

By Michael J. Martinson

Mine ventilation has been evolving as a separate field of study since the middle of the nineteenth century, and some practitioners might assert that mine ventilation has come of age as a discrete field in the last decade or two. Certainly the extensive literature now available on many facets of the subject, international congresses, the phenomenal upsurge of interest in mine ventilation in the United States of America since the passage of the 1969 Federal Coal Mine Health and Safety Act, and the existence of a virile mine ventilation society in South Africa with its own monthly journal all point in this general direction; on the other hand the lack of a rational design philosophy for ventilating mines suggests that mine ventilation may still be on the threshold of maturity. To generalise, many mines are still ventilated simply to comply with arbitrary statutory regulations, or with some ill- defined notion of reducing the risk of injury associated with the atmospheric environment in mines. Hazards in this category include oxygen deficiency, toxic gases and particulates, pathogenic gases and aerosols, explosive gases and dusts, and extreme climatic conditions. Although many mines are ventilated to abate the risk of a specific injury, there is inevitably a spectrum of latent and patent atmospheric hazards in every underground mine. The writer (Martinson, 1976) has previously drawn attention to the dearth of material on mine ventilation design in textbooks and technical journals, and to the overly simplistic approach sometimes adopted in the limited work published on the subject. The available material undoubtedly contains useful technical data and persuasive views, but seemingly could not be used to demonstrate the rational engineering approach to mine ventilation design advocated in the present paper. The range of papers presented at the 1975 and 1979 Congresses, and the diverse interests and affiliations of delegates, emphasize the multidisciplinary nature of mine ventilation. Easily recognisable topics include: Fluid mechanics Thermodynamics Heat transfer Flames and combustion Aerosol physics Radiation physics Geophysics and geomechanics Occupational diseases Epidemiology Industrial physiology Despite these heterogeneous connections there can be little doubt that mine ventilation is fundamentally an engineering field and not an off-shoot of some other branch of applied science. The distinction is important because mine ventilation has essentially developed as a form of ad hoc trouble- shooting, and in the process mining engineers have relied extensively on the assistance of experts drawn from other fields. Thus historically there has been limited scope for the application of rational design techniques, and personnel enlisted from scientific disciplines may not have had any previous experience in the intricacies of engineering design.

Jan 1, 1980