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By R. Dawson Hall

LONG regarded as nearly worked out, the anthracite region still shows promise of a hundred years of life, for means are being found to get bottom, top, pillar, and other coal that earlier generations disregarded as too expensive to mine. Rock drivages and, still more, machinery are making it possible to get such coal. Mechanical methods enable the owner of thin beds to mine these with profit, and the miner recognizes that he must permit the use of machinery or the inexorable laws of economics will deny him opportunity to work. E. L. Dana, Jr., well outlines this situation, which in the past year became definitely established. Stripping also is recovering, safely and inexpensively, coal that past generations regarded as too hazardous and costly for mining.

Jan 1, 1935

By S. K. Sarkar, B. Dr. Singh

INTRODUCTION India like USA has traditionally relied on bord and pillars as dominant underground method. Coal has generally been mined at shallow depth from relatively thick and horizontally bedded coal seams. These' factors contributed towards large scale adoption of bard and pillar. After nationalisation of coal industry in two stages in 1971 and 1973, large scale mechanisation and modernisation programmes were undertaken. Longwall mining was identified as one of the major that area for increasing underground coal production. The idea to introduce longwall mining was mooted to increase productivity and to promote conservation and safety. The nationalised coal industry has already worked about twenty longwall faces with different types of support. The tempo of introducing longwall is catching up and a number of longwall programmes with, Self advancing supports of different types and Capacity are in active stage of implementation. The country has not yet started producing mechanised Supports and therefore supports and machineries are being imported from U.K. and other countries of the continent. The of the major problem faced in the longwall projects is to choose suitable type and capacity of supports. The suppliers and manufacturers of these supports are not competent enough to choose and offer the right type and capacity of supports as their knowledge and information about Indian strata conditions are extremely limited. The Central Wining Research Station (Q.!RS), has undertaken a research programme for evaluating the rock mechanical conditions obtaining in the proposed longwall locales and has worked out a method for selection of proper type and capacity of supports on the basis of projected strata behaviour at the proposed locale. STRATA CCNTROL FAILURES Indian coal industry had made some attempts to introduce longwall caving in the early fifties after a working group set up by the Government of India had recommended its adoption to increase productivity and to modernise mines. Approximately 20 longwall faces were tried in the major Indian coalfields of Jharia, Ranigunj and Karanpurr between 1951 and 1968. The supports used consisted of 20T hydraulic props or 35140~ friction props. A number of these faces had suffered total strata control failures and a large number of support elements were lost. The Central Mining Research Station initiated a research programme to analyse these failures in the general background of behaviour of Indian coal measure strata at longwall faces. All the available data regarding the cases of failures were collected and physico-mechanical properties of overlying roof rocks were determined in the laboratory. Simultaneously, observations were continued to establish the behviour pattern of Indian coal measure strata at longwall faces. These studies were helpful in analysing the occurrences of collapse. BEHAVIOUR OF INDIAN COAL MEASURE STRATA The coal measure strata encountered in the principal Indian coalfields of Jharia, Ranigunj and Karanpura are in general strong in nature however, the immediate roof (mostly up to 1.5 to 2 m) in most of the cases is weak and false bedded shale. MI idea about the strength properties of immediate and overlying roofs may be obtained from the following table.

Jan 1, 1982

By A. S. Nowick, E. S. Machlin

ONE of the main criteria used to rate the heat-resisting properties of alloys is stress rupture.1 During a stress-rupture test a tensile specimen is held under a constant load at a constant temperature until it fractures. The chief measurement made during this test is the time required for rupture at the specific test stress and temperature. It was found empirically from a series of stress-rupture tests at a constant temperature that when the logarithm of the time for rupture is plotted against the logarithm of stress a straight line is obtained within experimental error.2~3 This method of showing stress-rupture data has been adopted by many investigators and the KACA.4 By interpolation and extrapolation from these plots, values of the stresses required to rupture the specimens (the rupture strengths) in 10, 100, and 1000 hr are obtained for specific temperatures. Alloys are then rated for a particular application on the basis of their rupture strengths at the rupture life that most nearly represents the application. Inasmuch as stress rupture is an important criterion in rating heat-resisting alloys, it would be advantageous to know the quantitative dependence of the time for rupture on stress, temperature, com- position, and structure. In order to obtain this information, an investigation was made at the KACA Cleveland laboratory during the spring of 1945. The theory of rate processes was used because it has been found to apply to certain processes such as chemical reactions, viscous flow, and creep that occur at a definite rate for given conditions. It was thought that stress rupture was such a process. An equation was derived that gives, for a given com- position and structure, the dependence of the time for rupture on stress and temperature. The investigation is part of a general program to provide information that will lead ultimately to the development of better alloys in order that the efficiency and power output of gas turbines used in aircraft propulsion can be increased. THEORY The theory of rate processes will first be discussed as a general theory. It will then be shown that if stress rupture of heat-resisting alloys can be treated as a rate process, certain equations must be satisfied. Later sections will then show that these equations are satisfied. General Theory of Rate Processes The theory of rate processes5 eveloped by Eyring and others has been applied to chemical reactions as well as to other processes such as viscosity of liquids and diffusion. In every case in which rate- process theory can be applied, there is a small subdivision, so that the macroscopic process is the net effect of all the small processes. This smallest subdivision is called the "unit process.'' For example, in a chemical reaction the unit process is

Jan 1, 1947

By W. D. MOTTER

THE following brief description of the status of operations of the Chile Exploration Co. at Chuquicamata, Chile; and of the plant as it exists today, points out the-great progress that has been made since the initiation of prospect drilling in 1912. During the 11 years which have elapsed since then, a group of small mines, eking out a 'precarious existence, has been consolidated into one large operating property,, taking high rank among the world's producers of copper. After a drilling campaign followed by a construction period, the plant first started operations in 1915. Since then production has been gradually increased, as world conditions permitted, until the present status has been reached.

Jan 1, 1924

By M. C. Fuerstenau, J. D. Miller

The response of calcite to flotation with saturated fatty acids and alkyl sulfonates of various chain lengths is presented. The amount of collector re-quired for flotation is shown to decrease systemati-cally with increasing carbon content from 8 to 12-carbon atoms per molecule. This systematic flotation response is correlated with the solubilities of the calcium-collector salts, which were established with a nephelometer. The 14-carbon collectors deviate from this systematic behavior, and no flotation is possible with the 16-carbon homologs. As determined by infrared analysis, the mechanism of collector adsorption involves a specific chemical reaction be-tween the collector and the surface. A reaction of the form CaCO3(s)+ 2 RCOO"=*=Ca(RCOO)2(s) + C03= is suggested. The pH of the system is also shown to be a most important parameter as it controls the carbonate, calcium, and collector ion concentrations in solution and thus controls flotation response. The importance of hydrocarbon chain length of collectors was recognized early, and various studies have been made on this aspect of flotation. Wilkinson, ' for example, noted that as the chain length of alkyl xanthates is increased, the amount of collector required for flotation of sphalerite is decreased. The same effect has been shown in the flotation of galena.2 Similar results were obtained when malachite3 and calcite4 were floated with various fatty acids. DeBruyn5 has shown that a similar phenomenon occurs when quartz is floated with amines at constant pH. Recently, Fuerstenau, Healy, and Somasundaran6 correlated this phenomenon with the van der Waals cohesive free energy of association of the hydrocarbon chains. It seems unlikely, however, that chain association could be involved in the sulfide and carbonate systems with the collector additions employed, especially with the short-chain xanthates. Rather, it would seem that the decrease in collector concentration with increase in chain length noted for flotation is related to the solubility of the metal-collector salt. The purpose of this investigation is to verify this premise and also quantify this phenomenon if possible. Calcite was selected for study with both alkyl sulfonates and saturated fatty acids as collectors. EXPERIMENTAL MATERIALS AND METHODS The collectors used in this investigation ranged from 8 through 14 carbon atoms per molecule. The fatty acids had a reported purity of greater than 99%. The sodium alkyl sulfonates were provided by the Marathon Oil Cot, Littleton, Colorado, and had the

Jan 1, 1968

August 10 to 14, 1914, inclusive Headquarters will be at the Hotel Utah. The following program of the meeting has been arranged y the Local Committees: Monday, August 10.-Members and guests will register at the Secretary's desk in Room C-38, Hotel Utah, and receive the official badges, booklets and programs of the meeting. At 2:30 P. M., there will be an organ recital at the Mormon Tabernacle, after which members and guests will be taken for a trip around Salt Lake City in sight-seeing motor cars. At 8:30 P. M., the ladies will assemble in the lobby of the Hotel Utah, where they will be met by the members of the Ladies' Entertainment Committee, and will be taken for an automobile drive about the city. At 8:30 P. M., a technical session will be held in the ballroom of the Hotel Utah. The following papers will be presented: F. W. BACORN: An Amendment to Sales's Theory of Ore Deposition. C. W. GOODALE: Drumlummon Mine, Marysville, Mont. I. B. JORALEMON: The Ajo Copper-Mining District. STUART CROASDALE: Leaching Experiments on the Ajo Ore. FRANK R. VAN HORN: The Occurrence of Bournonite, Jamesonite, and Calamine at Park City. HOWLAND BANCROFT: Dip Chart. M. N. ALLING: Ancient Auriferous Gravel Channels of Sierra County, California. B. S. BUTLER AND H. D. MCCASKEY: Copper Ores of the New London Mine. GEORGE A. PACKARD: Rope Idlers in the Raven Shaft. ARTHUR CROWFOOT: Development of the Round Table at Great Falls. FREDERICK LAIST AND A. E. WIGGIN: The Slime-Concentrating Plant at Anaconda. W, L, AUSTIN: The Treatment of Copper Ore by Leaching Methods. W. L. AUSTIN: Leaching Copper Products at the Steptoe Works.

Jan 8, 1914

By AIME AIME

LIFE will not be difficult for those who attend the fall meeting of the Petroleum Division at the Conoco Club, Ponca City, Okla., Sept. 30-Oct. 1. An attractive program to appeal to oil company executives and lawyers, as well as technologists, has been arranged and the Continental Oil Co. has contributed for the occasion the buildings, grounds and facilities of the club. E. 0. Bennett, Continental Oil Co., Ponca City, is chairman of the arrangements committee, and reservations for rooms and trips, requests for information, etc., should be sent to him.

Jan 1, 1932

By AIME AIME

EITHER the 2300 people who came to the Annual Meeting were in a better frame of mind or they were resigned to their fate, or it was a better meeting than usual. Whatever the reason, at the 1nstitute?s 148th meeting the attendance was better than ever before, things went more smoothly than in some previous years, and complaints appear to have been almost entirely absent. Patience was sometimes reauired but. almost without exception, it was forthcorning the well-known recession seems to have given many members enough leisure time to come to the meeting without depriving them of the tangible wherewithal to come.

Jan 1, 1938

By G. A. Wells

The consumption of barytes in certain paints, polyurethane foams, seamless flooring, glass, brake linings, plastisol gaskets for food containers, and in fluids used for gastrointestinal X-ray examinations relies on the unique properties of barium sulfate. There are no readily available mineral substitutes. Barytes are also the essential raw material for the manufacture of industrially important barium chemicals. High quality barite ore has become scarce throughout the world. Processing ore into quality end products is both capital and energy intensive. These factors have tended to limit availability and increase Prices which have encouraged the use of alternative or competitive materials and restricted market growth.

Jan 1, 1981

Iowa State College Ames, Iowa Iowa State Mining Society CARL S. NELSON, President NORMAN S. GEIST, Secretary K. A. PHILLIPS, Faculty Sponsor C. G. DRESSER, Counselor University Of Kansas Lawrence, Kansas University of Kansas Student Chapter of A.I.M.E. WALTER CROOK, President EDWARD C. MISHOU, Secretary E. A. STEPHENSON, Faculty Sponsor GEORGE M. FOWLER, Counselor K. A. SPENCER, Counselor .

Jan 1, 1942

By David J. Dunn

At a time when mill availability is at a premium, production costs are rising, and lead time for mill liner casting is a year or more, mill liner design is an important factor in ore grinding. Testing and selection of the optimum liner profile for a given set of mill operating conditions can improve mill capacity, reduce liner wear rate, and lengthen liner life. The mill liner that grinds best, lasts the longest, and costs the least is a necessity for economic mill operation. After testing four mill liner profiles for 3.96 X 3.65-m (13 x 12-ft) overflow ball mills, Climax Molybdenum Co. found that an improved design increased mill tonnage by 2.72 t/h (3 stph) while reducing finish grind by 1.7% minus 100-mesh, reduced liner wear rate, and almost doubled liner life.

Jan 12, 1976

(Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) Members who registered at Institute headquarters during July and August : R. H. Sweetser, Columbus, Ohio. C. R. Hill, New York, N. Y. Raymond Brooks, Goldfield, Nev. H. A. Morrison, Candor, N. C. Edward M. Shepard, Springfield, Mo. Frederick J. Patchell, Washington, D. C. Rudolf Gahl, Clifton, Ariz. Walter F. Pyne, New York, N. Y. Edmund von Maltitz, Pittsburg, Pa. Harvey B. Small, Mangangue, Colombia, S. A. M. K. Rodgers, Seattle, Wash. M. B. Cohen, Miami, Ariz. J. F. Erdlets, Jr., New York, N. Y. A. P. Watt, Newark, N. J. D. H. Ladd, Houghton, Mich. H. H. Stoek, Urbana, Ill. Roy F. Cornell, Santa Cruz, Cal. D. W. Brunton, Denver, Colo. W. B. Foote, Geneva, N. Y. C. S. Robinson, Youngstown, O. H. Sjogren, Stockholm, Sweden.

Jan 9, 1913

Truman H Aldrich '78 W. S Ayres '73 A. A Blair '75 Walter M Brodie '72 H M. Chance '74 Frederick G Corning '77 Henry S Drinker Founder Ernest F. Eurich '74 W. E. C Eustis '76 A Heckscher '79 Henry D. Hibbard '79 Julian Kennedy '79 William St. George Kent '72 Frank Lyman '77 John Markle '79 Samuel Mather '79

Jan 1, 1923

By John A. Gann

WITHIN a very few years magnesium has sprung from oblivion, from classification as a technically unknown, little appreciated, and expensive material to front-page importance in many fields of engineering. Bunsen may be considered the real founder of our present magnesium industry. In 1852; he prepared this metal by the electrolysis of fused magnesium chloride in a porcelain crucible. In the following years the electro¬lytic process became recognized as superior to chemical reduction methods and Germany became the world's chief producer, installing the first electrolytic magnesium plant in 1886. ' Thirty years later, national defense requirements, occasioned by the outbreak of the World War and the cutting off of imports, caused France, England, and the United States to begin production. Most of this magnesium was used for military purposes so the close of the war resulted in a large curtailment in production. A few companies, however, encouraged by the early success of the Germans and by the rapid developments taking place in aeronautics, and confident in the certain future and ultimate value of this metal, undertook extensive re¬searches in its production and utilization. A variety of production methods, both chemical and electrochemical, were investigated and some of them operated on a commercial scale. Reduction of the oxide with carbon at high temperatures and the electrolysis of the oxide in a fluoride

Jan 1, 1932

By Bieniawski, Z. T.

The importance of understanding the phenomena associated with rock fracture has long been fully appreciated in rock mechanics. This is clearly apparent from the special attention paid to rock fracture in the comprehensive papers published within the past four years. These papers present a picture of how the knowledge of brittle fracture of rock was gradually enriched and also show that what was often taken for granted three or four years ago is no longer considered as valid today.

Jan 1, 1972

By N. O. Taylor

THE failure, by swelling, of several cast aluminum-zinc, spiral, pump rods, used to circulate water in a constant-temperature bath, brought up the question as to whether the presence of tin in varying quantities would have any appreciable influence in controlling this action. Previous workers had found the same difficulty with aluminum-zinc alloys, due to their swelling in water or solutions of electrolyte^.^ It was known that pure aluminum was practically insoluble in concentrated sulfuric and nitric acids, presumably due to the formation of an oxidized film on the surface. Concentrated sulfuric acid had little or no effect on pure zinc and tin and concentrated hydrochloric acid would attack all three metals. These facts aroused curiosity as to the probable reaction of the ternary alloys of these metals, and tests were made to determine their resistivity to the action of common laboratory reagents. Samples, covering the entire range of the ternary series of aluminum, zinc and tin alloys, were made up from good grades of the commercial metals.2 The materials were melted, at as low temperatures as possible, in graphite crucibles in a gas-fired crucible furnace. Graphite crucibles were used in preference to clay, to prevent the absorption of silicon by the aluminum, as found by previous workers. The melted materials were stirred thoroughly with pine sticks in order to ensure complete mixing and the greatest possible freedom from oxidation, and were cast in sectional, iron molds giving bars % in. in diameter and 5 in. long.

Jan 1, 1927

(Members are urged to send in for this column, any notes. of interest concerning themselves or their fellow-members.) The following members registered at Institute headquarters during the month of May: Emil Gathmann, Baltimore, Md. Philip Argall, Denver, Colo. Albert H. Fay, Washington, D. C. A. C. Hodge, F.R.G.S., St. Austell, Eng. Alfred E. Barlow, Montreal, Canada. S. M. Marshall, Johnstown, Pa. B. C. Yates, Lead, S. D. Miltiades Armas, Paris, France. Leonard S. Austin, Salt Lake City. Albert Sauveur, Cambridge, Mass. Henry A. Wentworth, Boston, Mass. G. A. Reinhardt, Cambridge, Mass. Frank M. Leland, Mackay, Idaho. Fred Crabtree, Pittsburg, Pa. W. N. Crafts, Cleveland, Ohio. T. A. Rickard, London, England. Louis Hasbrouck, Kingston, N. Y. F. Lynwood Garrison, Philadelphia, Pa. F. V. Desloge, Desloge, Mo. S. B. Christy, Berkeley, Cal. E. C. Templeton, Palo Alto, Cal. H. A. Buehler, Rolla, Mo. L. D. Ricketts, Warren, Ariz. F. W. DeWolf, Urbana, Ill. J. E. Johnson, Jr., Ashland, Wis. Howland Bancroft, Denver, Colo. A. O. Granger, Cartersyille, Ga.

Jan 6, 1913

By Northcutt Ely

International developments affecting foreign in- vestments in 1960-61 were many, varying from region to region and differing with respect to various categories of investments. Total value of U.S. private investment abroad in 1960 was approximately $32.7 billion, an increase of $2.9 billion over 1959. Production and distribution of mineral resources was, by a sizeable margin, the most important function of American capital working in foreign countries in 1960. Investment in mining or petroleum interests totaled approximately $14 billion, or 42% of all direct foreign investment. In- vestments by industry for 1960 were as follows: Petroleum-10.9 billions, Mining-3.0 billions, Manufacturing-11.2 billions, Utilities-2.5 billions, other-5.1 billions. American investors found Canada and Latin America to be most desirable in 1960 with the greatest percentage of American capital in all areas centered in the petroleum and mining industries. The areal breakdown of total American investments is as follows: Canada-$11.2 billions, Latin America-$8.4 billions, Western Europe-$6.6 billions, Middle East-$1.2 billions, Far East-$1.2 billions, Africa-$.9 billions, other areas-$3.2 billions.

Jan 3, 1962

By F. Habashi

Conclusive evidence is given showing that the dissolution of gold in cyanide solution follows mainly the over-all equation A similar equation can also be written for the dissolution of silver. Theoretical derivation of the velocity equation for this reaction has been obtained, which describes quantitatively the experimental facts. The equation is as follows: where [CN-] and [O2] = the concentrations (in moles/ml) of cyanide and dissolved oxygen, respectively. DcN- and Do2 = the diffusion coefficients of cyanide and dissolved oxygen; 1.83 x 10-5 and 2.76 x 10-5 cm2 sec-1, respectively. A = the surface area of the metal in contact with the aqueous phase, in cm S = the thickness of the boundary layer; varies between 2 and 9 x 10-3 cm, depending on the speed and method of agitation. Rate being expressed in g. equiv. sec-1. INTRODUCTION During recent years a number of papers have been published on the kinetics of dissolution of gold and silver in cyanide solution.1,6 The authors agree that the rate of dissolution is diffusion-controlled, but disagree regarding the mechanism of the reaction. Some authors'-3 support the Bodlander equations: The apparently conflicting results, when critically reviewed, are concordant and lead to the conclusion that the proper equation for the dissolution reaction should be only Eq. 1. This conclusion is based on the following facts: 1) For every 2.2 equivalents of metal dissolved one mole O2 was consumed. 2) For every 1 equivalent of metal dissolved, 2 moles of cyanide were consumed.' 3) Hydrogen peroxide is formed during the dissolution of gold or silver, and for every 2.2 equivalents of metal dissolved, one mole H2O2 was produced.1,2 The fact that Kudryk and Kellogg4 did not detect H2O2 during the dissolution of gold should not throw doubt on the many affirmative reports of other investigators. Lund2 has shown that depending on the crystalline nature of the silver surface, (e.g. method of etching the sample) H2O2 may undergo catalytic decomposition heterogeneously according to: Further Kudryk and Kellogg4 carried out their experiments in the presence of 0.5% KC1 to achieve a greater electrolytic conductivity, and Matsudaira7 has shown that H2O2 is catalytically decomposed (homogeneously) in the presence of C1- ion in alkaline solution. 4) Experiments carried out by Boonstra8 and Lund2 showed that the dissolution of gold and silver respectively in KCN + H2O2 in the absence of oxygen was a slow process. Thus the reaction takes place to a minor extent only. Further kinetic studies showed that: 1) The rate of dissolution depends on the surface area of the metal in contact with the liquid phase, thus indicating that the process of dissolution is a heterogeneous process. 2) The rate of dissolution depends on the speed of stirring,5,6 thus indicating that the process is controlled by a physical phenomenon.

Jan 1, 1967

By Reaves. M. J.

The title of my talk, "What Happened to the Uranium Boom?" is old news. Certainly it is for this group. All of us that make our living in uranium know that the boom of the last half of the 1970's is over. U.S. production has been exceeding consumption by more than two to one. Mines and mills are closing and yellowcake prices have been dropping for over 20 months. The gloomy outlook for the industry in the near term has been well documented by soothsayers of various descriptions, your daily newspapers, and in the Nuexco Monthly Reports. I'd like to attempt to describe the next upturn in the market (speculate, really) based upon the clues we're seeing now. In order to do that, I'd first like to go over briefly, some of the market factors that contributed to the recent price drop and resultant production cutbacks, and then hypothesize on the way these factors are changing and will change. Market prices are greatly affected (maybe even entirely determined) by buyer perceptions. This is particularly true with uranium, because of the long lead times associated with nuclear plant construction and also with conventional mine/mill development. Before the price rise (say, 1975) utility uranium buyers believed that: 1) U.S. producers would have difficulty expanding to meet U.S. demand. 2) Australian and Canadian production was essential to avoid shortages in the early 1980's. 3) Uranlum prices would continue to rise as demand exceeded supply. 4) Enrichment capacity would become inadequate. It was thought necessary, therefore, to build enriched inventory in the early 1980's for use in the late 1980's. Artificially accelerated expansion of the uranium producer industry was necessary to accommodate anticipated enrichment demand. Current perceptions are largely the opposite. These are the beliefs that were held most of this year and late last year as prices dropped. 1) U.S. production is far in excess of domestic need. Contraction of the U.S. production lndustry is necessary. 2) Canadian and Australian supply is optional and not essential. Producers in those countries are expanding mainly by displacing higher cost production and not because they fill a void, 3) Prices may be essentially stable for some time. 4) Enriched uranium is in excess supply. That is 1981. 1982 is shaping up to look like this: 1) Prices will have bottomed out. (That is not Nuexco's opinion necessarily, by the way, but it is my opinion.) 2) There will still be substantial utility inventories, but fewer spot sales. 3) Canadian and perhaps Australian sellers will have made substantial sales in the U.S. and will be aggressively seeking more. 4) U.S. production will have been dramatically curtailed. U.S. utilities that wish to con- tract long term will have difficulty in finding domestic sellers. Concern will develop about the availability of U.S. production capability. Virtually all long term con- tracts signed will be with non-U.S. sellers. 5) An awareness will begin to develop among U.S. buyers that we are approaching a period of dependence upon foreign uranium (which will be true). The history of the uranium market has been one of dramatic changes and overreaction to those changes. The rapid price rise of a few years ago generated excess U.S. production capacity and the rapid price drop of the last two years will almost certainly result in too little capacity. It will soon be difficult for U.S. buyers to buy domestic material except on the spot market. The question is, "will they care?" The lack of demand, of course, is the underlying reason for the current poor health of the uranium industry. In 1972, 1973 and 1974 collectively, there were 105 nuclear reactors ordered in the U.S. That ordering rate was expected to continue and accelerate throughout this century. In 1975, 1976, 1977, 1978, 1979, and 1980 altogether, there were 56 more reactors cancelled than ordered. The net growth of our only customer since 1974 has been a negative 56. TO put this in perspective, if these 56 reactors were operating now it would more than double present U.S. uranium consumption. Underlying lack of demand is something that is simply not going to change in this decade. Time is going to be required. The NRC indicates that the maximum feasible number of new reactors that can be licensed each year is six. That would increase uranium consumption by only 10% per year. New reactors, if ordered tomorrow, would not generate new uranium demand until after 1990. Even so, United States' consumption of uranium will rise from the 1980 level of 18 million pounds per year, to

Jan 1, 1982