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By S. Stephen Uslan

The purpose of the study was to demonstrate the effect of positive reinforcement, specifically, social reinforcement (SR), on the frequency of eye, hand, and back injuries at four experimental salt mines. Injury data was collected from January, 1976, for the prePOMOST period and from the onset of training to September, 1978, for the post-POMOST period. All data was collected on a month-by-month basis. For the training period approximately 100 managers and supervisors from five plants were trained in the use of positive reinforcement for occurrences of "safe behavior." Each supervisor was also provided manuals and other supportive materials. Additionally, following training, all supervisors were provided some coaching experience to keep the knowledge and capabilities gained during training from being extinguished. The analysis showed significant injury reductions in two sites and no injury reductions in the other two. When the injury data was corrected for the additional man hours expended in the postPOMOST period, a third site showed reduction in injuries. Similar findings were shown when the experimental sites were compared to other sites in the industry. The results were interpreted to support the hypothesis that the application of social reinforcement is related to a reduction in injuries.

Jan 1, 1978

I feel a little like the Parson delivering his Sunday Sermon, chastizing his parishioners for not coming to Church. Those who need to hear me are absent.Nevertheless, I hope that if you agree with what I am about to say you will go forth and spread the word.We often hear of the impact mining has on the community. I prefer tonight to deal with the impact some community attitudes have on mining, and I want to point out that the results of these attitudes rebound to the detriment of our society. I want to deal particularly with regulation, taxation, and proflts.In a civilization whose standard of living is essentially dependent on an adequate and reliable supply of cheap metals and fuels, it should be evident to Blind Freddie that mining must be encouraged.I must express concern at the constraints inflicted on the mining industry by our community. We tend to blame Government for our difficulties, but we must recognize that Government acts merely as agent for the community. It is fair to say that in a free society, if Government actions do not reflect the demands of the electorate, then it doesn't stay the Government. It is important though for Government, in framing its policies, to ensure that it is not unduly influenced by the loud voices of minority groups.The people of our nation have every right to demand that our industry meet certain criteria to be allowed to operate. We all wish to live in a healthy and congenial environment, and to have our individual comforts protected. It is essential, however, that the community realizes that its demands on the mining industry are affecting Australia's prosperity.Each new regulation and each new tax or impost has its effect on investment, employment, and national revenue. Restraints result in an increase in costs which in turn raises the minimum value of a mineral deposit which is economically mineable. It results in minerals, which could be mined under more favourable circumstances, remaining in the ground, perhaps lost for ever.

Jan 1, 1978

By E. Allen Wendt

It is both a great pleasure and something of a challenge for me to have this opportunity to address a gathering encompassing such a wealth of expertise in the minerals field, It is particularly challenging because I have been asked to turn your attention from the relatively glamorous subjects of gold and money to the more mundane questions of our International commodity policy and the place of buffer stocks in that policy. However, these questions may be of more immediate importance for our economic interests at home and Abroad. I can testify that the problems affecting international commodity markets and the possibility of international action To resolve those problems are matters of real concern to Washington as well as to your industries,

Jan 1, 1978

By George H. Bodfish

This paper begins with a short history of air compressors, emphasizing their "roots" in the mining industry. It then describes the types of compressors available, including reciprocal, the various rotary positive-displacement compressors, and the centrifugal. The advantages and disadvantages of selecting a certain type of compressor over another are enumerated, considering customer requirements and operating costs, among other factors. Guidelines to operation and maintenance are discussed, including installation, monitoring and maintenance procedures. Finally, the paper addresses itself to future trends, with special attention being given to the system concept, the increasing use of rotary compressors, power consumption, reliability, packaging and noise attenuation.

Jan 1, 1978

Council and Standing Committees, 1976-1977 President: Dr M. D. G. Salamon. Vice-Presidents: P. A. von Wielligh and Dr M. G. Atmore. Honorary Treasurer: J. K. E. Douglas. Immediate Past President: Dr R. E. Robinson. Members of Council: J. D. Austin, E. Collier, C. T. Fenton, J. A. Holmes, Dr P. R. Jochens, Prof. R. P. King, Dr D. G. Krige, Prof. F. Q. P. Leiding, D. G. Malan, C. T. Shaw, D. A. Viljoen, R. A. von Maltitz. Chairman, Witbank-Middelburg Branch: E. J. Jackson. Chairman, Orange Free StatelKlerksdorp Branch: A. N. Shand. B. Past Presidents Serving on Council: R. J. Adamson, H. Britten, J. K. E. Douglas, R. C. J. Goode, Prof. D. D. Howat, Dr J. P. Hugo, D. G. Maxwell, Prof. R. P. Plewman, V. C. Robinson, P. W. J. van Rensburg. Ten Council meetings were held during the year, and the standing and sub-committees held seventy-one meetings. Standing Committee Chairmen: Membership, Dr M. G. Atmore; Technical Programme - Metallurgy, J. A. Holmes ; Technical Programme - Mining, C. T. Shaw; Vacation School - Metallurgy, Prof. R. P. King ; Vacation School - Mining, Dr D. G. Krige ; Awards, Dr R. E. Robinson; Excursions, C. T. Fenton; Adjudi¬cation, Dr R. E. Robinson; Constitution, Rules and Policy, Dr R. E. Robinson; Mines and Works, C. T. Shaw; Education, Dr R. E. Robinson; Pyrometallurgical Discussion Group (Convenor), Dr J. B. See; Phoenix National Committee, Dr R. E. Robinson.

Jan 1, 1978

By D. L. Paulson

Electric furnace smelting of blister copper directly from copper precipitates (cement copper) was investigated by the Federal Bureau of Mines. Copper concentrations in five different lots of cement copper in the investigation ranged from 62.5 to 82.5 wt-pct. Laboratory-scale smelting tests were made in a 50-kva electric-arc furnace to establish the reductant and flux requirements. Best recoveries were realized by adding 60 pct of the carbon required to combine with the contained oxygen in the cement copper. Operating parameters established during the laboratory-scale smelting tests were used successfully in smelting 20 tons of cement copper during 12 pilot-scale tests in an 800-kva electric-arc furnace. Over 98 pct of the contained copper was recovered as blister-grade metal. The projected energy consumption for a commercial-size furnace was 380 kwhr per ton of cold charge.

Jan 1, 1978

By K. W. Edwards

The formulation of a theoretical basis for the evaluation of in-situ coal through the use of geophysical logs is outlined. This involved the development of an approach to the interpretation of resistivity in environments having multiple conductive and non-conductive components. Utilizing this approach and other conventional interpretation techniques, a program was developed yielding accurate determinations of the in-situ percentages of coal, water and ash for the evaluation of coal deposits. Basic information obtained from the CWA program can be utilized in numerous aspects of total mine planning . Some examples of the practical application of this method are included.

Jan 1, 1978

By J. C. Motz

With ore grades continually decreasing and finer mill feed requirements, it becomes increasingly important to have the capability to handle the larger tonnages economically. With the 10 ft. Standard capable of reducing 1,633 metric tons per hour (1,800 short tons per hour) to 80 percent passing 50 MM (2 inches) and the 10 ft. Short Head following to produce a mill feed of all minus 12 MM (1/2 inch) at a rate of 608 metric tons per hour (670 short tons per hour), we feel significant savings will be realized in installation and operating costs. The largest concentration of cost in the secondary and tertiary crushing stations is the building itself that houses the process equipment. An example of the savings to be attained can be seen from an examination of a 40,820 metric ton (45,000 short ton) per day crushing plant. A total of nine 7 ft. Symons Cone crushers is used to generate 12 MM (1/2 inch) ball mill feed. The average center distance between units is 6.1 M (20 feet) and allowing a 6.1 M (20 feet) nominal distance from the centerline to the wails, the building becomes 61 M (200 feet) long. For this production rate, four 10 ft. Symons Cone crushers would be required. With the 10 ft. crushing plant requiring a center distance spacing of 7.6 M (25 feet), the building length totals approximately 38 M (125 feet). Construction costs vary depending on location, but a reduction in building length from 61 M (200 feet) to 38 M (125 feet) will result in estimated savings of between $2,500,000 and S4,000,000. While the 10 ft. Symons Cone has been involved in a number of feasibility studies for some time, the Process Machinery Division of Rexnord commenced detail design work on the 10 ft. Cone crusher in 1972. For comparison purposes, the 10 ft. and 7 ft. capacities are given in Table 1.

Jan 1, 1978

The Aluminum Company of America (Alcoa) announced plans to shut down production at the remaining two potlines at its Point Comfort, Texas primary aluminum smelter due to the increased costs of natural gas. Total capacity of the facility, which had been partially closed since 1976, was 185,000 tons per year representing 3.6 percent of current capacity in the United States. There were practically no price movements in March on 99.5 percent aluminum ingot, with producers at 53¢ per pound and dealers, 48¢-48.5¢. BISMUTH The March selling position of U.S. producer metal was held at $3.50 per pound. In contrast, east coast dealers and traders adjusted their quotes from $2.55-$2.60 to a wider range of $2.40-$2.60.

Jan 1, 1978

By J. H. Adkins

The goal of the project reported in this paper was to make recommendations for changes in roof bolting procedures and bolter design that would reduce roof bolter accident rates. To that end the project identified the major hazards associated with each task a roof bolter operator per-forms, normalized task accident frequencies. by the time spent on each task, reviewed equipment design features and operating procedures related to the identified hazards and developed recommendations for equipment and procedural changes that would reduce, if not eliminate, the hazards. The research steps completed during the project were: a. A review of related literature and re-search including roof bolting time studies b. The collection and analysis of 1975 accident data pertaining to roof bolter activities c. The normalization of the accident frequency data on the basis of time/task data d. A review of roof bolting equipment e. The development of a field data collection instrument f. The selection of mines for bolter observations g. The collection of field data h. Data analysis and problem specification i. The development of recommendations for corrective measures

Jan 1, 1978

By Robert R. MacLachlan

New underground mining technology is evolving through the use of large-diameter bore holes containing individually restricted charge weights. This article presents summary observations on cube-root scaling trials using single and rows of charge blasting in sand and in frozen ground. These observations have some bearing on the evolving underground practice, especially where charges of appropriate geometry are used.

Jan 1, 1978

By James E. Lawver

The agriculture industry has made great strides during the past decade to increase agriculture yields through increased use of fertilizers. Increased use of fertilizers may prevent or at least delay mass starvation due to the alarming increase in world population. Phosphate was added to soil as a plant nutrient in the forms of calcined bones at least 2 000 years ago, (1) and man has used phosphate minerals as a source of fertilizers in one form or another for at least 100 years. During 1977 the world produced about 116 million metric tons of phosphate rock, with about 86% used for fertilizers and another 4% for animal feed supplements. More than three-fourths of the total production comes from the United States, Morocco, and the Soviet Union. From a mineral beneficiation point of view, the major sources of phosphate rock and the methods of beneficiation can be classified as follows. Marine deposits not containing appreciable carbonate minerals, marine deposits requiring a francolite carbonate mineral separation, igneous deposits not containing appreciable carbonate minerals, and igneous deposits, requiring an apatite carbonate mineral separation.

Jan 1, 1978

By Richard N. Zimmer

This paper discusses the installation of corrugated steel linings in bored raises at Inco's Thompson Mine. The procedure for the installation of these linings is outlined and the relative advantages are compared with conventional methods of ground support. Future trends in the use of corrugated steel products are then discussed.

Jan 1, 1978

For the sixth year in a row, the value of nonfuel mineral raw materials produced in the United States set a new record, reaching almost $17 billion in 1977. Data provided by the Bureau of Mines show that the 1977 value of domestic nonfuel mineral production exceeded the 1976 value, $16.7 billion, by 2 percent. The $17 billion worth of minerals was the basis for approximately $770 bill ion worth of processed materials of mineral origin. Output of metals decreased $360 mil lion in 1977, while that of nonmetals increased $670 million. Of the 22 metals produced, output of 12 increased, and the value of 13 increased. Among the 46 nonmetallic minerals produced, the quantity of 27 increased, and the value of 34 increased.

Jan 1, 1978

By J. Baicker

A two-inch diameter probe containing an intrinsic germanium detector, a canister-type solid cryogen cooling system, cooled FET preamplifier, linear amplifier, high voltage supply, analog-digital converter, microprocessor, buffer memory, bidirectional cable link, and all power supplies has been designed, assembled and tested. A surface support vehicle was designed, built and outfitted. A mini-computer system was constructed and preliminary software developed and tested. A special handling system for a Cf-252 neutron source was designed and has been ordered. The entire system (less the neutron source) is ready for its first field tests. Lab description of the system is presented.

Jan 1, 1978

Since mid-July, most domestic producers have been marketing 99.5 percent unalloyed aluminum ingot at 53-57 cents per pound. Dealers in the United States have recently quoted ingot at 52.3-52.8 cents. On October 2, London Metal Exchange will trade aluminum, selling contracts on a cash and a 3-month basis. New York dealers were quoting August ingot at 52.3 52.8 cents. The Bonneville Power Administration announced that, effective December 20. 1978, electric power rates charged primary aluminum producers in the Pacific Northwest would be increased The increase (equivalent to about 4 cents per pound of aluminum produced) will raise the average rate to about 8.7 mills per kw-hr compared to 3.2 mills per kw-hr.

Jan 1, 1978

By John S. Lagarias

When ore bodies are faulted or mill feed turns refractory, mining managers and engineers act vigorously to convert imminent failure into eventual success. The recent proliferation of onerous "environmental" regulations and restraints is likewise a threat to successful mining enterprise, in some ways more insidious and dangerous than the problems presented by natural obstacles. The regulatory burden has become so heavy that a pall of pessimism covers much of the mining enterprise. In this paper we frankly recommend a Pollyanna approach, making not just "the best of it" but directing the whole environmental process: first, to improve our planning, engineering, and operating procedures; and, second, to demonstrate the need for modification of laws and regulations which are intolerably burden-some to both the mining industry and the public. It is customary for government officials and environmentalists to point out how great are the new environmental regulations and how successfully these have improved the natural environment in particular and the quality of life in general.

Jan 1, 1978

Entering June, U. S. producer pricing of 99.5 percent unalloyed aluminum ingot was divided at 53-57 cents per pound. The Kaiser Aluminum and Chemical Corp. took the initiative and raised its June 1 ingot values by 4 cents to 57 cents. Consolidated Aluminum Corp. announced plans to increase ingot prices by 4.5 cents per pound to 57.5 cents per pound effective May 15. Dealers increased their May ingot quotes by 1.5-2 cents to 50-50.5 cents. CADMIUM While producers in the United States kept May cadmium at $2.25-$2.50, dealers increased their quotes by 15-30 cents to as high as $2.15.

Jan 1, 1978

By P. J. Noakes

Remote and isolated, located in a frigid, hostile environment, the Black Angel mine in Greenland had to create a warm social environment which would help attract and retain a stable work force of miners and support staff. The high cost of personnel turnover plagues many mines and, when the mine is inside the Arctic Circle, accessible by helicopters which are highly vulnerable to unpredictable weather conditions during the long, dark winters, the potential costs of personnel turnover become critical factors in the success or failure of the mining venture. Manpower planning should start from the date the engineers begin the technical design of the new mine. The plan should include provisions not only to ensure an adequate, skilled work force, but also to ensure a stable work force of people who are happy enough in the mining environment to want to remain, take their vacation and return to work at the mine. The skilled work force was assured with training courses of four months, designed to produce highly specialized underground workers from unskilled Danes and Greenlanders supported by trained Swedish and other Scandinavian miners. The stable social unit was assured by plans the primary attribute of which had to be flexibility. The accommodation changed from shared accommodation with communal washroom facilities to single accommodation with private washroom facilities. A recreational director was hired to help the workers make use of elaborate recreational facilities. A closed-circuit TV and radio system was installed to operate as a private broadcasting system using taped programs originally broadcast on European TV networks or developed by the mine personnel themselves. The liquor rules were changed and the mine manager became a licensed innkeeper responsible for the orderly operation of the Black Angel Bar in accordance with the Danish laws governing the services of a public bar. The result is a relatively stable work force. Some 35% of the people have more than two years' service with the company, Greenex A/S, and some 62% complete 10 months of service.

Jan 1, 1978

By F. Halverson

"The theory of flocculation usually is in a state of flux, involves many diverse phenomena, and is complex and sometimes contradictory in details. Instead of attempting a general discourse, I shall discuss selected observations made at our Stamford Laboratories, which impinge on theoretical aspects in two somewhat distinct areas of flocculation. Since some of you many not be familiar with flocculation, and :.n order that we all attach the same meaning to the jargon used, I first would like to review briefly a generalized picture of what goes on.Assume we have a suspension of particles in water, with a distribution in the sizes of particles. The surfaces of the particles interact to some extent with the water--· tending to alter the extent of hydration, may generate some ion exchange, all being somewhat variable with time--developing a surface condition which is very complex in details. We refer to this suspension as the ""substrate.""In the usual situation, if the suspension is allowed to stand quietly, the large particles settle out first, with somewhat smaller particles settling more slowly, and then there is a portion of very fine material which takes a long time or doesn't settle out at all. This resistance to settling t~ the very fine particles results from many factors, but all relate back to the size and density of the particles, to their surface properties, and to the other components in the aqueous suspending medium."

Jan 1, 1978