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By C M. Zammit, N Cook, F Reith, C L. Ciobanu, J Brugger

The role of biological agents in the gold mining industry is currently limited to the use of microorganisms in bioleaching and bioremediation. However, there is a variety of possibilities in which biotechnology could aid the mining industry in the future. In this article we discuss the potential for the development of these novel biotechnologies and the role they can play in the exploration for new gold deposits, the processing of ores and the post-mining remediation of sites. The development of these biotechnologies has been enabled by rapid advances in our molecular-level understanding of the role microorganisms play in the solubilisation, dispersion and precipitation of gold. An understanding of the distribution of microbial species in soils overlying mineralisation can be utilised to develop bioindicator systems that assist with gold exploration. An in-depth knowledge of how microorganisms interact with gold complexes is being used to develop in-field biosensors, supporting exploration. Processing technologies may be improved based on advances in our understanding of the interactions between microorganisms, ore minerals, cyanide and gold. For instance, cyanide-producing microorganisms are being investigated for use in in situ leaching of gold. In turn, the use of cyanide-utilising microorganisms for the degradation of cyanide is being explored. Combined, the implementation of these biotechnologies in the gold mining sector may revolutionise the industry, leading to greener, more efficient exploration for and extraction of gold.CITATION:Zammit, C M, Cook, N, Ciobanu, C L, Brugger, J and Reith, F, 2013. Possible future applications of biotechnologies in the gold industry - a prospective approach, in Proceedings World Gold 2013 , pp 233-244 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By M. S. Moats

In the 1990?s, Técnicas Reunidas developed the Modified ZINCEX® Process to recover zinc from ores and secondary materials. The heart of this process was the use of solvent extraction to produce purified zinc electrolyte instead of traditional zinc dust cementation. This development was commercialized by Reunion Mining and Anglo American for primary ore at the Skorpion mine in Namibia with the first SHG zinc produced in May 2003. Horsehead Corporation through Horsehead Metal Products, Inc., its wholly owned subsidiary, is presently commercializing the MZP for the treatment of Waelz oxide. This paper will review open source information about the lessons learned and process modifications that have occurred at Skorpion over the past decade. It will also provide an update on Horsehead?s facility being constructed in Rutherford County, North Carolina.

Feb 23, 2014

By Daan Maijer, Wade Marquardt, Robert MacKay, Steven Cockcroft, Farzaneh Farhang Mehr

"To comply with the new Corporate Average Fuel Economy (CAFE) standards, the automotive industry is aiming to reduce weight and increase the power and efficiency of small displacement engines through the application of forced induction technologies. As an example, there are now several 2.0 litre turbocharged engines in production, producing in excess of 240 hp. To meet the need for improved fatigue properties in the engine blocks used in these high-output engines, a new water-cooled chill technology is under exploration at UBC in partnership with General Motors and Nemak. A series of experimental techniques were used to assess the capability of the new chill to extract heat from an A319 casting in the vicinity of the main bearing bulk head. The results show that this method has the potential to achieve a reduction in secondary dendrite arm spacing thus meeting the new microstructural specifications for these engines.INTRODUCTION The automotive industry is working to meet the stricter efficiency requirements laid out within the CAFE (Corporate Average Fuel Economy) regulations (Bastani, 2012; Cole, 1995; Mackay, 2011; Miller, 2000), while at the same time not sacrificing performance. One approach is to increase the use of lightweight materials, which leads to a decrease in the overall vehicle weight and fuel consumption (Cole, 1995; Mackay, 2011; Miller, 2000). Other approaches include smaller displacement engines and gas-electric hybrid drivetrains. However, one trend that is becoming clear, is a greater emphasis on force induction gasoline engines. This allows for weight reduction to be achieved with smaller displacement engines without sacrificing performance. One consequence of this approach is that the engine block materials are subject to higher in-service thermal and mechanical cyclic loads (Cole, 1995; Miller, 2011; Heysler, 2001) The fatigue properties of an alloy are strongly affected by a number of the, as-cast, microstructure features including, Secondary Dendrite Arm Spacing (SDAS), porosity and eutectic lamella spacing (including intermetallic ß-Al5FeSi platelets) (Mackay, 2010a; Mackay, 2010b; Viet-Duc, 2015; Casellas, 2005). It is generally accepted they can act as fatigue initiation sites and that a reduction in their size will result in an improvement in fatigue performance. For a given alloy chemistry, one of the key parameters affecting the length scale of all three is cooling rate (Mackay, 2000)."

Jan 1, 2017

By H. A. Schrecengost, H. R. Gil, Alfred Clarkson, E. H. McCleary

Much has been written and many discussions have been held concerning the prevention of accidents in coal mines , and considerable progress has been made in eliminating hazards to the health and safety of underground workmen . Although much progress has been made in the reduction of injury rates in the Pennsylvania anthracite field , the injury rates for the anthracite mines of Pennsylvania are generally higher than the average for coal mines in the United States as a whole , because the mining conditions , including the safety problems , in the Pennsylvania anthracite fields are more complex than in other coal fields of the United States . Several factors contribute to this extremely difficult problem , among which are : Multiple - vein mining , steeply pitching measures , folds or faults , hard smooth floors underneath the veins , and the remining or reclaiming of pillars in severely crushed , broken ground . In the early days of the Pennsylvania anthracite industry , only the more productive veins were mined , and this resulted in bypassing those veins that were relatively thin and those containing considerable proportions of impurities . However , the development of modern coal - preparation equipment , improved marketing conditions , and the adoption of mechanical equipment , such as the various types of conveyors and scraper loaders , have made possible the recovery of the thinner and poorer veins . Furthermore , in the early days , little or no attempt was made to recover the coal pillars , usually owing to the great amount of virgin coal available . Consequently , much of the anthracite produced within the last few years has been recovered by second and third mining and frequently by fourth mining - in areas where operations had been suspended for many years . In such areas , the coal veins and intervening strata are usually crushed as the result of gradual subsidence , which intensifies the hazards incidental to roof control , haulage , ventilation , and mine gases . Moreover , the use of coal - cutting equipment is not practicable in most anthracite mines because of. the inclination of the veins and because , in crushed -ground areas , the faces must be advanced slowly and for short distances at a time to permit the erection of timber sets and the placing of forepoles to support the roof and sides . Thus , the slow process of mining brought about by these conditions has resulted in the production of only 0.424 ton of anthracite for each man- hour worked , as compared with 0.753 ton? for each man - hour worked at other coal mines in the United States . A summary contained in Bulletin 462,8/ a publication of the Federal Bureau of Mines , reveals that the rate of fatal injuries in the Pennsylvania anthracite industry was improved from 13.47 deaths per million tons produced in 1870 to 3.88 deaths per million tons mined in 1942. During the period March 16 , 1942 to January 1 , 1947 , the fatality rate was reduced from 3.88 to 2.87 deaths for each million tons mined . On the million man-hour basis , the rate of fatal injuries was reduced from 1.643 to 1.130 and the nonfatalinjury rate was lowered from 119.01 to 83.12 during the same period . The improvements made in both the fatal- and nonfatal - injury rates have required the cooperation of the workmen , the mining companies , and the State and Federal inspection departments . Many individual mines and companies have achieved commendable safety records which contributed greatly to the over - all average for the industry , particularly during the 1942-47 period . One of the most outstanding of these is the Continental mine of the Continental -Archbald Coal Co. , a member of the Moffat Co. Interests .

Jun 1, 1948

By R. M. Cunningham

Asarco operates one of the largest individual copper electrolytic refineries in the world at Amarillo, Texas. The feed for this refinery is a mixture of anodes produced at Asarco smelters and copper purchased t?om a number of primary and secondary sources. The variation in feed makes it imperative that the refinery practices state-of-the-art quality control to minimize the effects'of unwanted impurities in the electrolytic refining process. In late 1993, a plant designed to sigru6cantly reduce the antimony and bismuth levels in the electrolyte was commissioned. The purification plant uses ion exchange technology in conjunction with a novel strippiing system developed by Zeneca Specialties (U.K.). The strippiing system permits the recycling of the eluant and thus avoids the extremely high costs of stripping with conventional reagents. In addition, the environmental impact of treating the eluant for recovery of antimony and bismuth is minimized. This paper outlines the development of the technology and, in particular, describes the operational practices and improvements at Amarillo since the commissioning of the plant.

Jan 1, 1997

The research described in this report was conducted under a cooperative research agreement between the U.S Bureau of Mines Twin Cities Research Center (TCRC), Cleveland-Cliffs Inc. (CCI), and three operations in Northern Michigan managed by CCI: the Empire and Tilden surface taconite mining operations, and the Central Shops maintenance facility. All of these operations are in or near Ishpeming, MI. The Human Factors Research Group at TCRC is responsible for designing, planning, and conducting the research, and reporting on the findings. This project was carried out in order to investigate the high prevalence of back injuries being experienced by workers employed at the three CCI Northern Michigan sites, In an analysis of Company accident records for workers employed at these sites, it was determined that back injury problems confronting the CCI sites mirror those confronting the entire mining industry.

Jan 1, 1994

By J. R. Patts, J. P. Rider, J. A. Organiscak, A. B. Cecala

"NIOSH recently completed a 15-month study at an underground limestone mine crusher booth which evaluated three research parameters: (1) the effectiveness of a single-filter filtration and pressurization system for improving the air quality inside the operator booth, (2) comparing the effectiveness of ? > 99 and ? > 95 experimental prototype filters in the system, and (3) evaluating the use of three different pressure monitoring devices to determine the performance of the filtration and pressurization system over time. The protection factor was quantified monthly using particle counters in the respirable dust range (0.3–10 µm), and gravimetric dust samples were gathered at the beginning and end of the overall study. Under static conditions and after outlier removal, the single-filter filtration unit installed offered a protection factor between 8 and 216, depending on the filter type and loading condition. The particle counting analysis shows that the ? > 95 filter offers a protection factor greater than 4-times that of the ? > 99 filter when evaluated over 60 minutes. The booth pressure monitors provided data that proved to be a valid indicator of system performance over time. INTRODUCTION Designed and installed correctly, enclosed cabs, operator booths and control rooms offer mine workers protection from physical hazards, such as flying rock, debris, and noise, as well as a more comfortable environment in regards to temperature and humidity [1]. But while it may be easier to quantify whether the A/C unit is working (measuring the temperature) or observe whether the cab offers protection from flying debris, it can be somewhat more difficult to quantify its performance in reducing respirable dust hazards. For over 15 years, NIOSH has been conducting applied research to improve the air quality inside of enclosed cabs of mobile equipment [2-5]. This work has led to the identification and mathematical modeling of enclosed cab filtration systems [6]. The same principles that govern the performance of filtration systems on mobile equipment are applicable to stationary enclosures such as operator booths and control rooms [1, 7]. Stationary enclosures are similar to enclosed cabs; however, the volume of the work area can be significantly larger. In addition, workers who perform their duties in stationary enclosures tend to stay within the room for a greater percentage of the day, as opposed to workers on mobile equipment who may enter and exit frequently. Structural integrity can be easier to maintain as well, as there is typically less vibration and stress placed on these compartments as compared to mobile equipment. In addition to offering protection from dust and flying debris, enclosures must ensure that workers have a healthy supply of fresh air to avoid elevated levels of CO2, which are known to cause headache and dizziness, impairing cognitive function. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) states that enclosures should have no more than 1,100 ppm of CO2 when outside levels are 400 ppm [8]. In addition, the American Society of Agricultural and Biological Engineering (ASABE) recommends a minimum airflow for enclosed cabs of at least 42.5 m3/hr (25.0 cfm) per person [9] to ensure an acceptable level of CO2."

Jan 1, 2017

By C. Blawert

In previous studies of various HPDC magnesium alloys we found that the corrosion properties of the skin are inferior in comparison to the bulk, However, this is surprising as one would expect better corrosion properties for the finer microstructure of the skin, In a more detailed study using 2 and 6 mm thick sections from HPDC AZ91 step plates, the corrosion results of the original skin, the slightly removed skin and the bulk were compared, Indeed, the corrosion measurements including potentiodynamic polarization, long term polarization resistance measurements and electrochemical impedance spectroscopy (EIS) revealed a lower corrosion resistance of the original as-cast skin. An explanation for this corrosion behavior was found, on the one hand, in the microstructure concerning especially the amount and distribution of the 13-phase and, on the other hand, in the composition, including the distribution of the most important alloying element Al and of some impurities such as Fe.

Jan 1, 2005

By D. M. May

"Cut-and-fill mining is a stoping method that has been widely utilized in the mining industry over the past forty years. It took preference over shrinkage methods at Levack in the early 1930sbecause of its safety aspects; i.e., prompt support of the stope sidewalls, good working floors and better accessibility to support poor back areas. In addition, higher recoveries of ore were possible because of the flexibility of the method in that silling could take place easily at any horizon; low-grade ore could be sorted and left in the stope as fill and certain zones of rock could be left unmined. With modern techniques, a steady production rate can be established, as filling and mining can be carried out stimultaneously.AIthough there are numerous variations of cut-and-fill mining throughout the world, this paper reviews the original type of mining, with modifications and improvements through the years to present modern practices, with the Levack West operation appearing to be the most productive at this time. Stoping efficiencies have also increased substantially from the original 10 tons per manshift to the present 55 tons per manshift.The paper also outlines the many improvements that have been made with respect to mucking and ground support operations; from hand mucking in a single stope to the use of frontend loaders and haulage trucks in fully accessible stope complexes; and from timber props to roof bolts of various types. Although present methods are extremely satisfactory, experimentation is continually being conducted to improve safety and productivity for future mining.IntroductionThe major mining operations of the Ontario Division of Inco Limited are located in the Sudbury Basin (Fig. 1). Around the rim of this geological formation and within 30 miles of the City of Sudbury are nine producing mines and one ' open pit operated by the company .Ore production currently approximates 11.5 million tons per annum from underground and open-pit operations. Underground mining methods include sub-level caving, shrinkage, cut and fill, undercut and fill, blasthole and vertical retreat. The Levack Complex, the main plant of which is the central Levack Mine, produces 11,000 tons per day.The first prospecting in the Levack area, in 1887, was conducted by James Stobie, who examined rock cuts along the route of the Canadian Pacific Railway to the northwest of Sudbury. However, it wasn't until 1913 that operations commenced at Levack under the Mond Nickel Company."

Jan 1, 1981

By G. V. Fernandez

Sociedad Minera Cerro Verde S.A.A leaches secondary copper sulfides. In recent years, the mine has introduced innovations that have improved the management of mineral crushing, agglomeration, curing, and leaching. The crushing plant, for example, uses the concepts of degree of balance and percentage of time in an operationally balanced state which, displayed in real time, facilitate more intensive and uniform utilization of the crushers. High agglomerate quality is ensured with the correct dose of moisture, which is adjusted to the changing characteristics of the mineral through the use of electrical conductivity measurements. The amount of acid used for curing the agglomerate is also adjusted by using quality control information. Finally, the stockpile irrigation regime is managed using the criteria established by the "Lixiviant Request Rate", which optimizes the addition of leaching solution, creating such benefits as faster recovery, and reduced acid and energy consumption.

Jan 1, 2007

By Plato Malozemoff

While this conference is dedicated to the examination of "Challenges in Mineral Processing," the broader aspect of the pursuit of this subject is Research and Development in the Mining Industry. When I was asked to speak at this symposium, I hesitated to accept. While my early schooling, training and professional occupation were in the field of this symposium, it was so long ago that I no longer feel competent to contribute anything of interest to you except perhaps for a limited historical perspective, which most of you probably already know. However, it might be worthwhile to explore the more general aspect of research and development from the viewpoint of management, as this is the stance from which I dealt with the subject for the last 30 years or so. While most managements generally have a positive view of research and development, few of the leaders in the mineral industry have actually had the personal experience of doing research for a long enough time to have obtained a full understanding and the feel for its place in the long-term technological innovation that our industry must foster. I graduated from the University of California in Berkeley with a Bachelor of Science degree and a major in metallurgy. It was during the great depression of the thirties, and it was difficult to obtain a practical job in the industry. I got a scholarship at the Montana School of Mines and received a Master of Science degree in ore dressing under Professor A. M. Gaudin, followed by another year with him pursuing research. Anyone who studied under him, or knew him well, would assert that this was a unique experience. Gaudin had a brilliant mind and a profound respect for science and the scientific method. He wished to know the scientific basis for every new technological appli-

Jan 1, 1989

By Michel Ruel

"This paper describes how to make advanced control choices when difficult processes need improvement. The decision-making process involves choosing between a rules-based approach and a model-based approach as well as weighing benefits and drawbacks, complexity and simplicity, investment and results. This paper will present briefly each solution: basic control, advanced regulatory control, model predictive control, and expert systems such as fuzzy logic controllers and neural networks. The article then proposes a decision tree for selecting the most appropriate approach. A table will compare usage, development, commissioning, maintenance and lifecycle costs for each approach. Finally, conclusions and suggestions will summarize the methodology.INTRODUCTION Advanced process control (APC) is a popular topic. How can one decide whether advanced control should be added to an existing system? Advanced control is used to improve performance, stabilize production, handle constraints, protect equipment and manage grade changes. Most plants use feedback controllers, usually PID (proportional, integral, derivative) controllers. It is common to develop special control schemes to handle more complex processes. In classic PID process control, a controller brings a single value close to a set point using a single manipulated variable. On the other hand, APC brings several values close to optimal targets simultaneously using several manipulated variables. APC's four main strategies are advanced regulatory control, model predictive control (MPC), fuzzy logic and neural networks. Simple solutions are always preferred. Complexity will be increased if performances (production, quality, etc.) are below par. Profitability analyses should be conducted to validate project viability. Needs—not trends—should dictate choices! Before increasing complexity, it is important to define needs, goals, technical support, budget, etc. All these approaches entail strengths and weaknesses. Building a project based on technology rather than needs spells trouble."

Jan 1, 2014

By Christopher Tucker, Marcello Veiga

Social issues are increasingly recognized as significant inhibitors to mineral development projects. Increasingly social risk is being recognized as a key factor determining the success of a mineral investment. Groups opposed to a mine for social or political reasons often use environmental impacts, real or perceived, to prevent mine development. These risk factors depend largely on cultural perceptions of mining activities and must be understood as such in order to be appropriately managed. A first step to addressing social issues is inclusive, transparent and meaningful engagement of stakeholders. This process allows stakeholders to understand what the other parties value in order to collectively establish a common currency for development and the creation of mutual value. Expanding the scope of benefits and values a mine can bring is of increasing importance to mining companies who typically consult outside specialists remote from the mine site and late in the development timeline for this purpose. Training technical staff, engineers and geologists, who make initial and ongoing contact with local interests, in a holistic approach to mine development is crucial to successful and economic mineral development projects. Further extending this conversation to the general public, media governments and non-governmental organizations is a necessary step in developing a meaningful discourse on the benefit of mining activities.

Jan 1, 2014

By D. R. Wilburn

This summary of international mineral exploration activities for 2012 draws upon information from industry sources, published literature and U.S. Geological Survey (USGS) specialists. The summary provides data on exploration budgets by region and mineral commodity, identifies significant mineral discoveries and areas of mineral exploration, discusses government programs affecting the mineral exploration industry and presents analyses of exploration activities performed by the mineral industry. Three sources of information are reported and analyzed in this annual review of international exploration for 2012: 1) budgetary statistics expressed in U.S. nominal dollars provided by SNL Metals Economics Group (MEG) of Halifax, Nova Scotia; 2) regional and site-specific exploration activities that took place in 2012 as compiled by the USGS and 3) regional events including economic, social and political conditions that affected exploration activities, which were derived from published sources and unpublished discussions with USGS and industry specialists.

May 1, 2013

By L Ventura, M Almond

The Pueblo Viejo project in the Dominican Republic installed an innovative sample system on its reverse circulation (RC) drilling rig during commissioning and subsequent commencement of operations. As knowledge of the orebody increased with mining and plant production, cost pressures became apparent that raised questions concerning the continued use of RC drilling versus blasthole sampling for ore control.To justify the continued use of RC drilling for grade control, an in-depth study was undertaken to determine the quality of the sample and prove its value-add to the operation.To investigate the differences in sample quality, a complete bench trial was initiated across both ore pits to compare RC drill results with blasthole assays on a side-by-side basis. The results indicated that based on ore block comparison between RC and blasthole sampling, RC identified an additional 20 per cent of high-grade (+ 4.5 g/t Au) ounces.Previous work indicated that Au, Ag and Cu were all elevated in the drill fines at Pueblo Viejo (Goers and Almond, 2012). This previous test work did not consider the quantity of fines in an RC sample therefore new test work was undertaken to include particle size distribution analyses. This study would determine if the inclusion of fines in the sample was occurring and compare the quantity of fines in the sample against other sample systems and blasthole samples.Comparisons between RC samples and blasthole samples indicate that for the RC samples a range of 30–35 per cent of the sample passed 300 mesh as compared to blastholes where the range of the sample passing 300 mesh was 15–30 per cent.This paper includes a case study on the importance of accurate samples and how they have impacted throughput through the pressure oxidation process plant at Pueblo Viejo. The accurate samples provided by RC allow for improved stockpile and blending strategies, showing the importance of accurate samples to manage risk and create value, against the perception that savings can be made at the risk of poor sampling performance.CITATION:Almond, M and Ventura, L, 2017. Adding value with reverse circulation drilling at Pueblo Viejo, in Proceedings Tenth International Mining Geology Conference 2017, pp 277–284 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By Carl-John Grävare

This paper deals with some of the systems and equipment that are being developed and/or are in use in Scandinavia. The main subject is the development of loading tests on the piles using monitoring equipment. This paper also describes ground improvement using lime-cement columns, expander body piles and steel core piles.

Jan 1, 2000

Universities have had a long history in the education of geology graduates, Analysis of this history reveals a record of success, as judged on a world basis. However there have been significant changes in the last 20 years that have impacted on the ability of universities to continue to provide their traditional style of geology education. These changes have increased in the last 10 years. In the teaching side, there has been a change in expectations. Additionally the increasing workload decreases the value of each academic to perform the tasks needed by the new education. In the area of research, the funds provided have continued to decline, in both real and absolute terms, and it is now necessary for universities to seek out funds to pay for their postgraduate research. Additionally, the universities have slipped into the error of what cahn only be termed "academic incest", and research student mobility has decreased to an undesirable level, stifling initiative and new ideas in a number of cases, The only solution is for Government monies to be "directed" - ie that the postgraduate student must leave his or her original university in order to receifve the research stipend/scholarship. On the government front, the government and its agencies have not adequately analysed and recognised the need for the redirection of education and research funds into the needy areas of science and technology, especially those that related to the minerals area.

Jan 1, 1986

By J. Bartrum

Kidston Gold Mines is a 14 000 tonnes per day rated operation located 280 kilometers west of Townsville in Queensland. The principle shareholder is Placer Development Limited. Kidston's orebody consists of 44.2 million tonnes graded at 1.79 g/t gold and 2.22 g/t silver. Production commenced in January, 1985, and despite a number of control, mechanical and electrical problems, each month has seen a steady improvement in plant performance to a current level of over ninety percent rated capacity.

Jan 1, 1985

By Irwin H. Cornell

BRIEFLY stated, the history of the St. Joseph Lead Co. is the story of how a group of men, working for ten years as officers without salaries and stockholders without dividends, developed a small mine in Missouri into what became a large and prosperous corporation. Their courage and faith in the scattered surface deposits of lead coupled with the management's engineering vision and sound financial judgment should prove an inspiration to present-day mining operators and investors. In 1717, John Law's company, known as "The Company of the West," was formed in France and letters patent were granted, for a period of 25 years by Louis XV, for exploration in the Mississippi River Valley. One of the underlying purposes of the expedition, headed by Mr. Renault and Mr. La Motte, a French metallurgist, was development of the lead mines in the area now known as Southeast Missouri.

Jan 1, 1947

By Carl E. Bagge

It is easy for a coal spokesman to relate to the theme of this meeting--that the decade of the 1970's is pivotal for the mineral industries. For the coal operator, this period is crucial. The coal industry, according to most energy forecasters, must gear its production machinery to meet a sharp rise in the demand for coal--in this decade to sustain inevitable boosts in electricity output, and in the next to start supporting a big new domestic synthetic fuels industry that is already in the formative stage. The logic of that projection flows from a combination of hard circumstances--proved reserves of domestic fluid fuels are dwindling, the hope for bountiful and cheap nuclear power must be indefinitely deferred, and the threat of long-term fuel imports to the national interests is becoming starkly visible. Only coal, with its assets of abundance, security and versatility, offers the nation an adequate and immediate lift out of its current energy crisis. A hard-won expansion of coal production made the critical difference between local power load-shedding and major area blackouts in 1970, the year the energy crisis went public. Coal will have to play that same key role, not just through this pivotal decade but through the turn of the century. But the logic of fuel demand apparently does not always extend to supply. The coal industry has had a huge production job laid out for it by the energy statisticians, but up to now the energy policy-makers have not followed through with the aids and inducements that the coal operator urgently needs to do that job well and completely.

Jan 1, 1972