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I. PRESIDING OFFICERS. At all Business meetings of the Institute the President, or, in his absence, the Vice-President, or, in the absence of both of them, any other member of the Board of Directors to be chosen by the meeting, shall preside. At all other meetings of the Institute the President of the Council or, in his absence, one of the Vice-Presidents, if present, shall preside II. ORDER OF BUSINESS. At each Business meeting of the Institute the order of business shall be as follows 1. Reading of minutes of preceding meeting. 2 Report of the President. 3. Report of the Treasurer. 4. Report of the Secretary. 5. Election of Directors. 6. Election of Members of the Council. 7. Reports of Standing Committees. 8. Reports of Special Committees. 9. Special Orders 10. Miscellaneous business. This order of business may be changed by a vote of a majority of the Members and Associates present in person or by proxy. The usual parliamentary rules shall govern all meetings of the Institute except in cases otherwise provided by the Constitution or the By-Laws. At all sessions of the Institute other than business meetings, the order of proceedings and the time of adjournment, shall rest in the discretion of the presiding officer

Jan 1, 1917

By S. Shapiro, R. G. Ames

Background Research on the respiratory health of coal miners has focused predominately on the relationship between coal mine dust exposure and ventilatory function impairment (Lapp et al., 1972; Jacobsen, 1976), on the prevalence of coal workers' pneumoconiosis (Lainhart et al., 1969; Morgan et al., 1973), and on coal miner mortality (Ortmeyer et al., 1974; Rockette, 1977). Lesser attention has been paid to the effects of other mining exposures. For example, underground exposure to diesel exhaust emissions (Reger et al., 1980; Ames et al., 1982,1984). An omission in US coal mining research, however, has been identified by the US Office of Technology Assessment (OTA) as the failure to study the effects of inhaled polyvinyl chloride (PVC) thermal decomposition and combustion products (Seltzer, 1979). These products may be released in the mine environment by cable fires, cable explosions, smoldering cables, and conveyor belt fires. In addition to the OTA concern, recent findings of chronic respiratory conditions and other health complications resulting from exposure to PVC decomposition and combustion products in firefighters (Peters et al., 1974; NBS, 1980; NIOSH, 1982; Wallace, 1982), and in survivors of several large scale PVC-fueled fires (Dyer and Esch, 1976; Wallace, 1981, 1982), add immediacy to the concerns. PVC decomposition and combustion PVC decomposition is initiated at temperatures far below ignition (Hartstein and Forshey, 1974; Wallace, 1981). Hence, exposures to decomposition products from smoldering cables may be important health hazards in addition to cable insulation combustion products. Hydrochloric acid (HCL) appears to be the principle toxic substance from the thermal decomposition of PVC since up to 60% by weight is released as HCL (Barrow et al., 1979). HCL is released both as a gas and as an adsorbant on soot particles (Stone et al., 1973), thus allowing penetration of respiratory defenses. In addition, laboratory results indicate that phosgene (carbonyl chloride), a potentially lethal gas, may be produced in significant quantities from electrical arcing of wires covered with PVC insulation (Woolley, 1971; Brown and Birky, 1980). Health concerns related to PVC Toxic effects resulting from high level exposures to PVC pyrolysis and combustion products in animals (Cornish and Abar, 1969) and in humans (Wallace, 1981) is beyond question. Analyses have reported acute, or short-term, health effects resulting from exposure to PVC decomposition and combustion products (Peters et al., 1974; Polakoff et al., 1975). Recently, however, several studies have found that acute effects are often followed first by apparent healing, and then by delayed chronic effects. This pattern of consequential respiratory involvement among persons involved in major PVC-fueled fires has been noted in firefighters, specifically the 1975 New York Telephone Exchange fire (Dyer and Esch, 1976; Wallace, 1982), and the survivors of the 1977 Beverly Hills Supper Club fire (Wallace, 1981). An obstructive syndrome (low FVC and FEV1) was seen in 15% of workers three months following fighting a PVC-fueled fire (Colardyn et al., 1976). Long-term respiratory symptoms seen in studies of survivors of PVC-fueled fires include the bronchitis symptoms of cough and phlegm, and lung dysfunction (Wallace, 1981). Additional support for the thesis of longer-term respiratory effects resulting from PVC-fueled fires is derived from the finding that four persons who initially survived the Beverly Hills Supper Club fire died within nine months of the fire of severe respiratory impairment (Wallace, 1981).

Jan 1, 1986

By E. H. Ahrens

This paper deals with the responsibilities of an operating geologists and the relationship of operations to exploration. It should be of interest to those soon to enter the profession, those new to mining geology and as a review to more experienced geologists. Subjects discussed include detailed geologic mapping, sampling, core logging, assaying, selection of proper map scale, posting geological and assay data, section preparation, identification of ore controls, delineation of development drill targets and geologic hazards, models and the very important topic of salesmanship. Methods and ideas, proven valid in vein, pyrometasomatic replacement and porphyry copper deposits are presented. Hopefully, these will smooth the path for new members of our profession.

Jan 1, 1984

By P. Marier, T. R. lngraham

The kinetics of the sulfation of MnO,, MnzO3, and Mn3O4 in SO,, SO3, and O, mixtures was examined and the descending order of sulfation rates at temperatures near 400°C was found to be Mn,O3 > MnO, > Mn3O4. The respective activation energies for the thermal decomposition of MnO, and Mn,O, are 39 and 47 kcal. At 900°C, the thernzal decomposition of MnSO, to MnzO3 is slower than that to Mn3O4. The respective activation energies are 62 and 51 kcal, respectitely. MANGANESE is used to improve the hot workability of steel in the proportions of approximately 13.5 Ib of ferromanganese per ton of steel produced. This requirement accounts for about 95 pct of its large industrial market in North America. The remaining 5 pct is used in the battery and chemical industries. In most North American ores, the percentage of manganese and the manganese-to-iron ratio are not suitable for the direct production of ferromanganese. Hence, most of the North American requirements for manganese are satisfied by importing ore. Typically, many of the studies done on native low-grade manganese resources have been directed toward the production of ore substittes" and the recovery of manganese from open-hearth slags.3 Of the wide variety of processes which have been proposed, the most popular involve compounds in the Mn-S-O system. The thermodynamic properties of manganese and its compounds were reviewed by ah' in 1960 and, more recently, lngrahams discussed the thermodynamics of some of the reactions involved in the Mn-S-O system at normal roasting temperatures. The conditions for producing manganese sulfide during the reduction roasting of manganese sulfate are discussed by Fuller and Edlund.9 A novel scheme was proposed recently by zimmerley7 for utilizing waste sulfur dioxide from stack gases to recover the manganese from ocean-mined manganese nodules. Very little of the work published on manganese compounds has been related to reaction rates. Singleton et 1.' studied the rates of reaction on the MnO-C and Mn7C3-3MnO systems and observed linear and parabolic kinetics respectively in the systems. Tatievskaya et a1.' studied the low-temperature reduction of Mn&, MnO,, and Mn& in HZ and CO, and reported activation energies in the range 1628 kcal. In this paper, the rates of some of the decomposition and formation reactions involving MnSO4, MnOz, MnzO3, and Mn3O4 will be examined after the conditions for the thermodynamic stability of the individual compounds have been designated. CONDITIONS FOR STABILITY OF MnSO4, MnOz, MnZO3, AND Mn3O4 The areas of stability for h'hSO4, MnOz, MnzO3, and h3O4 were established from the data of Mah4 and Ingrahams and are shown in the predominance area diagram,10 logpq- logpsq, in Fig. 1. The diagram is drawn for two temperatures, 700°K, solid lines, and 1100°K, dotted lines. The sketch for the lower temperature includes the conditions likely to prevail in the Zimmerley patent7 when manganese nodules react with sulfur dioxide and that for the higher temperature indicates the conditions for recovering MnzO3 or Mn3O4 from MnSO4 during a roasting reaction. From the fact that the boundary between the areas of stability of MnOz and hSO4 at 700°K is parallel to the abscissa, it is evident that MnOz and SO2 should react together to produce MnSO4, irrespective of the oxygen pressure in the system. If the source of sulfur for sulfation were from waste flue gases, it is likely that the oxygen content of the gas stream would be more than sufficient to oxidize any MnsO4 to MnzO3, 107 atm of O2 required, or even to convert any Mnz03 to MnOz, 0.02 atm OZ required, prior to sulfation. At 1100°K, the diagram indicates that MnSO4 may be converted directly to either MnzO3 of Mn3O4, depending upon the prevailing partial pressure of oxygen. When the gas stream contains more than 1 pct Oz, logpq = -2, only MnzO3 would be recovered from an experiment done under equilibrium conditions. At oxygen partial pressures of less than 1 pct, one would expect to bring about a reversible exchange between MnSO4 and Mn3O4 by appropriate adjustment of the partial pressure of SOZ. These various reactions will be described in the subsequent kinetic experiments.

Jan 1, 1969

By Mowry Bates

The following example of the practical application of engineering geology is of interest in that it demonstrates the advantage of keeping accurate records of all wells, whether drilled by onn's self or by others, together with the advantage gained by gathering such data during the process of development. The fault described was found in the autumn of 1915, during the hurried development caused by the discovery of the famous Gusher Bend pool in Red River Parish, Louisiana. The writer was at the time employed by one of the operating companies as geologist, and the example is a portion of the routine work. Location The oil fields of northern Louisiana and east Texas are located in Caddo, Bossier, De Soto and Red River Parishes, Louisiana, and Marion County, Texas. A very narrow strip of the eastern portion of the latter is productive. The producing oil pools are known as the Caddo Field, in the northern part, and the De Soto-Red River Field, in the southern. The two fields are 60 miles apart. There are several gas fields between them, but no important supply of oil has been found, though there are several producing wells in the Anona chalk, locally called the Chalk Rock, in the Elm Grove gas field in Township 16 North, Range 11 West (see Plate 1). General Geologic and Structural Features The general geology of northern Louisiana has been excellently described by A. C Veatch in Professional Paper No. 46, U. S. Geological Survey; by G. D. Harris, Bulletin No. 429, U. 8. Geological Survey; and later by George C. Matson and Oliver B. Hopkins in Bulletins No. 619 and 661C, U. S. Geological Survey.

Jan 1, 1920

By Robert Livermore

THE Smuggler-Union mine is in the upper San Miguel mining district near Telluride, Colo., and the group of claims now forming the property were first worked in 1875. Development was slow until the completion of the railroad in 1890, when it pro- ceeded rapidly. In 1896 four hundred stamps were dropping in the district, the production was $3,000,000. A geologic section of the country rocks, where ex-posed by erosion from the valley at 8700 ft. to the sum-mit at 13,500 ft., shows the sedimentaries made up of flat-bedded sandstones and conglomerates, of the Jura-Trias, superimposed at 9700 ft. by a series of bedded rocks of igneous origin, andesites and andesite breccia. These rocks extend 3000 ft. to the rhyolite capping, largely fragmentary, which occurs at 13,000 ft. The ore horizon is, so far as known, contained in the 3000 ft. of' andesite and breccia. The Smuggler vein is a fault fissure which, with its extension to the north, the Humboldt vein, contains one of the longest continuously mined orebodies in the world. The length of the orebody so far developed is approximately 9000 ft. The width of the valuable part of the vein is, however, narrow, 3 ft. being the average, and the depth to which it has been worked up to the present is 2500 feet. There are several crossing and branch veins, all of which have been more or less productive. Of these, the so-called Flat vein, discovered in 1915, with its pro-duction of nearly 2,000,000 tons, has been the most important. This vein joins the Smuggler at an acute angle in the northern section of the property. North of the junction the two veins lie side by side and form an orebody of importance which gives promise of exten-sion with depth. The valuable metals of both the Smug-gler and Flat veins are gold, lead and silver. In the former silver is more important than lead, and the reverse relation holds in the latter.

Jan 3, 1928

By A. G. Willard

Quantification of size, shape and composition has been one of the more difficult areas for those concerned with fine particle processing of coal.' Image analysers fed by optical microscopes and by scanning electron microscopes possessing backscatter detectors and energy dispersive facilities now offer techniques to improve the speed and precision of previous methods. This paper discusses the methodology and procedural difficulties associated with the microanalysis of coal. Photographs show display quality on the image analyser monitor and the equipment mentioned. Data illustrating several of the procedures are included. The major portion of data for design and operation of plant for fine particle processing depends on information regarding size, shape and composition of granular material. The lower limits of particle sizes become more important as lower grade deposits are mined. Because of the trends towards treatment of finer materials, the use of image analysis offers advantages in time, effort and accuracy. As energy becomes more critical, the above applies especially to coal processing. The Zeiss Microvideomat 2, a leading member of the second generation instruments, is now available for image analysis. There is a precision television scanning system with monochrome camera, display, control panel and central processor (see Figure 1).

Jan 1, 1980

On Wednesday evening, Jan. 27, 1915, were held in the auditorium of the Engineering Societies Building the inaugural exercises of The Engineering Foundation, established by the United Engineering Society. The initial gift to the Foundation of $200,000, made by Ambrose Swasey, Past President of the American Society of Mechanical Engineers, was formally accepted at this time. So far as known this is the first instance of a foundation devoted to engineering purposes. This meeting con-stituted also an appropriate tribute to the generous gift made to the Foundation and gave opportunity for expression of the satisfaction and approval which are felt by engineers everywhere at the establishment of a means of promoting the good of mankind through the work of the engineer along the broadest lines. Gano Dunn, President of the United Engineering Society and Past President of the American Institute of Electrical Engineers, acted as presiding officer, and on the platform were seated representatives of the three societies constituting the United Engineering Society, and of the American Society of Civil Engineers. Members of the four societies and many other friends interested in the profession composed the audience.

Jan 3, 1915

By J. M. Smith, G. P. Willhite, J. S. Dranoff

Heat transfer rates were measured in sandstones with flow of gases perpendicular to the direction of energy transfer. Effective thermal conductivities ker ranged from 0.7 to 1.7 Btu/(br)(ft)(°F). The contribution of the solid phase appeared to be the most important in these consolidated materials, although the thermal conductivity of the gas had some effect. The velocity of the gas through the pores of the sandstones had no influence upon ker up to values of 168 lb/(br) (sq ft) in agreement with data obtained for unconsolidated beds of glass beads. The present results indicated that gas mixing, and hence heat transfer by convection in the pores, is less for perpendicular transfer of energy than when fluid flow and energy transfer are in the same direction. HEAT TRANSFER PERPENDICULAR TO FLUID FLOW IN POROUS ROCKS Heat transfer in porous media with pore sizes in the micron range depends upon the fluid in the pores and the geometry of the solid phase. The best characterized system is a bed of solid spherical particles. Heat transfer in this system has been studied extensive1y (Ref. 8 summarizes the literature up to 1959) when the pores contain stagnant fluid. When the fluid is in motion the directions of flow and energy transfer have an effect on the heat transfer rates, as demonstrated by comparing the work of Willhite, et al l3 for perpendicular flow and that of Kunii and Smith9 for parallel flow of energy and fluid. For perpendicular flow, no increase in effective thermal conductivity ke was noted up to mass velocities G of 77 lb/(hr) (sq ft). In contrast, for parallel flow ke, increased with G in the same range of flow rates. These higher values of ke in the direction of flow also have been observed3,4,10 in beds of larger particles, 0.1- to 0.5-in. diameter. For beds of consolidated materials, such as porous rocks, data are not available for these compar- isons, although Adivarahan1 reported results for the parallel case. Hence the primary objective of this work was to measure ke values for perpendicular flow of fluid and energy in porous rocks. Of interest also was the variation in effective conductivity with fluid velocity. APPARATUS AND PROCEDURE In the experimental method, a constant heat flux was applied to the inner surface of an annular section of the porous rock. By cooling the outer wall, a temperature gradient through the annular sample was established and measured with thermocouples placed within the sample at various radial positions, and at three elevations (A,B.C). The location of the 2-in. O.D., 3.75-in. long sample in the apparatus is shown in Fig. 1. Fluid entered the bottom (1) of the 3-in. I.D. (approximate) steel shell, flowed upwards through the sample and out at the top (3). pressure taps (2,4) were used to check the permeability of the sample. The energy flowed radially from the centrally-located electric heater through the sample and was absorbed in the water-cooled jacket. The samples studied were naturally occurring sandstones from different locations with the properties given in Table 1. These materials are identical with those used by Adivarahan 1 for the parallel flow of energy and fluid. Prior to use they were refluxed with toluene to remove hydrocarbons and leached with distilled water to remove soluble salts. Each sample was visually examined and discarded if large nonhomogeneities, such as cracks or stone particles, were noted. Eight copper-constantan thermocouples were inserted in holes drilled radially into the sample with

By P. Somasundaran Discussion by Knut L. Sandvik

Knut L. Sandvik (Mining Engineer, Mineral Dressing Laboratory, Technical University of Norway, Trond-heim, Norway) — The discovery that adsorption at solid-liquid interfaces is influenced by adsorption at other interfaces may prove very fruitful in the further development of flotation theory. Having reached the same conclusions as P. Somasundaran in some experiments with amine hydrochlorides, I would like to offer more direct evidence of the interfacial adsorption mechanism based on surface tension measurements and adsorption studies.' This evidence was derived from flotation tests carried out in a Hallimond tube at neutral pH and 60°C. The amount of amine solution and quartz surface were chosen to insure measurable concentration changes during flotation due to adsorption. Adsorption data for

Jan 1, 1969

By F. R. Jones

T Tahawus, N. Y., National Lead Co. operates the MacIntyre development. Here the world's largest titanium mine produces 5200 long tons of ore per day and pours 8000 long tons of waste rock over its dumps. Concentrated ilmenite is sent by rail to National Lead Co. pigment plants, and a second product, magnetite, is sold to steel producers in raw form or is agglomerated and shipped as sinter. Several earlier attempts had been made to produce iron from the deposits, which have been known since 1826. These attempts failed, chiefly because of titanium impurity. In 1941 the present owners re-established the operation for production of war-scarce ilmenite, and the impurity became the main product.

May 1, 1956

By Kendall E. Born

Production of crude oil in Tennessee during 1937 was slightly over 37,000 bbl., an 85 per cent increase over the preceding year and the highest since 1928. Closer cooperation between the operators and the State Division of Geology has resulted in more accurate data than have been possible for the past few years. Such cooperation is most desirable, especially in this state, which has no law requiring the filling of drilling permits, logs, and production figures. The increased production for the year has resulted from discoveries of four small pools in the shallow district of Clay and near-by counties. The most promising of these began production late in 1937 and consequently has had little effect on the 1937 total. These discoveries, along with renewed activities in some of the older areas, have increased the production for Clay and adjoining counties from less than 5000 bbl. during 1936 to over 21,000 bbl. in 1937. The Mississippi lime production in Scott and Morgan Counties declined from 16,335 bbl. in 1936 to 14,644 bbl. during 1937. While the decline curve on this production has been gradual, some of the wells are over 20 years old, and it becomes necessary to look for other favorable structures in this general region if increased production is to be obtained or past production maintained. The only natural gas marketed off the lease in Tennessee during 1937 was in Morgan County, where a small amount was furnished for the town of Sunbright and its immediate vicinity. The gas occurs with the oil in the Boone Camp field and small amounts were put on the line from the near-by Coon Hollow and Seabolt pools. Development There were 59 wells spudded in during 1937, of which 18 were drilling or only temporarily shut down on Dec. 31, 1937. Of the 41 completions, 17 produced oil, 5 were gas wells of undetermined quantity, and 19 were dry or near-dry holes. The flush production on the new wells totaled about 1300 bbl. per day. The more important wildcats are listed in

Jan 1, 1938

By H. D. Pearsall

It is well that the usual system for supplying water at high pressure purposes of hydraulic mining possesses serious disadvantageense, delay and large annual repairs. Where plough work possible, the first expense of the ditch is moderate; but it is verynree years before the work is solid and the ditch water-tight, lxPenditure for repairs being needed during this time and greaf water occurring. Moreover, in the course of a long ditch, it happens that part of it has to traverse a diffi cult country fluming, masonry, or other expensive construc tion is necessich makes even the first cost high. The life of flumes is also) The ad visa if pumping water instead of supplying by gravity has therefore been suggested, when sufficient water-power for the purpose oping happens to be available. But the expense of the requiuchinery and its complication, which involves skilled attend expensive wear and tear, has hitherto pre vented. The author ever, having been called upon to make plans and estimates for Lulic works for an extensive placer-mine in Colo rado, has such in devising pumping arrangements which are free from these sections, and are in fact estimated to cost less than half what a din the usual plan would cost. Several incidental advantages in plan also accrue, which will be referred to more particularly be The works placer-mine have not yet been carried out, on account of final arrangements, but in the meanwhile an hy draulic 'engineilar to that designed for the mine, has been con structed and so work for other purposes in England; and in order to explane plan which I have recommended for working the placer-mine will' describe this, which is actually at work, in preference to cibing the one which is not yet constructed. The engine machine acts on the principle of the hydraulic ram

Jan 1, 1888

By JOHN S. HEARDING

ON the Minnesota Ranges, 600 million tons of material have been moved in the past three years to produce 172 million tons of direct-shipping iron ore. Increasing wage rates and cost of equipment and supplies, coupled with the larger amount of waste material to be moved in comparison with the quantity of ore make it imperative that tile industry adopt all practices and methods which will enable it to move earth at progressively lower costs. Drilling. Prior to and during the war practically all blastholes drilled were 6-in. in diameter and put down by drills using strings of tools weighing from 2000 to 3000 lb. Present trends indicate that heavier drilling equipment making 9-in. holes wit11 3000 to 6000 lb tools will be more economical. Holes up to 12 in. diameter will be made with this equipment. Forging and hardening practices for bits to increase footage is receiving attention. One manufacturer expects to market 9-in. bits having sintered carbide inserts in the reaming and cutting edges. Oxygen and oil to burn holes in the rock are being tested for making blastholes at a considerably greater speed than can be obtained with a blasthole drill on the same size hole. To dale, however, the cost has been prohibitive.

Jan 1, 1949

By A. Lubinski, J. E. Hansford

Jan 1, 1965

Jan 1, 1966

By Chris Weyand

Throughout the past 40 years we have been drawing inevitably closer to the conclusion that coal will be our chief source of energy. Our reserves of natural gas and petroleum, on which we depend, are dwindling. Knowing that we will soon reach our physically extractable limit of these energy sources. The US government has created many incentives to encourage energy companies to transfer technology and resources from natural gas and petroleum to coal. Such encouragement is stimulated through taxation methods. Coal mining engineers deal mainly with production, which involves planning and design throughout the acquisition, exploration, development, production, and reclamation of a mine. Though taxation is not one of the areas analyzed by the engineer, it should be considered and understood as it is involved in the mine life cycle. This paper will discuss coal taxation in the five stages of mining and will explore certain tax saving decisions.

Jan 1, 1983

By Octavio G. Echavarria

HISTORY The Santander Mine is located on the western flank of the Central Andes of Peru, about 100 miles northeast of Lima, at an elevation of 15,000 ft. This complex sulphide orebody, whose predominant minerals are sphalerite and marmatite with recoverable amounts of galena and chalcopyrite, was discovered around 1920. In 1956 Compania Minerales Santander, a subsidiary of St. Joe Minerals Corp. acquired the property. Construction of the camps, concentrator and power facilities started in 1957. The mine, at first an open pit operation, and mill began production in January 1959. The initial capacity of the mill was around 120,000 short tons per year (stpy). Production has increased steadily to about 312,000 stpy at present. Production statistics are shown in Table 1. [ ]

Jan 1, 1970

By B. Van Voorhis

Successive changes have been made in stoping methods at the Magma mine. Factors that have made these changes advisable are: vein width, heavy and swelling wall rock, abnormal rock temperatures, ventilation, labor costs, timber costs, mining speed, and labor-saving mechanical developments. Additional localized conditions, such as low angle post-mineral faulting and selective mining, have also made changes necessary. A stoping method with enough flexibility to meet most of these conditions has been in use for the past ten years. The Magma Copper Co. was organized by the late William Boyce Thompson in 1910 and acquired by purchase and location several groups of contiguous claims, among them the Silver Queen property. The Hub and Irene claims acquired in this purchase cover the apex of the vein, and all stoping done up to 1920 was from these two claims

Aug 1, 1956

By Jerry L. Taylor

Utah Power & Light Company is an electric utility serving approximately 1.8 million people in Utah, Idaho, and waning. In order to supply coal to fuel power plants, Utah Power & Light awns three mines in central Utah. Planning for these mines is aided by a computer program developed by the staff mining engineers. This program, when supplied with the pertinent seam and mining configuration data, calculates the time to mine each section. This allows the planning engineer to estimate accurately the time required to extract pillar sections or develop longwall panels. The program's greatest benefit, however, is its ability to allow the engineer to examine quickly, different combinations of possible mine layouts to determine the most efficient plan. Computer aided mine planning has been used at Utah Power & Light Company since 1979, and has significantly improved the accuracy and quality of mine planning.

Jan 1, 1983