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COLUMBIA LOCAL SECTION STANLY A. EASTON, Chairman, FREDERIC KEFFER, Vice-Chairman, L. K. ARMSTRONG, Sec.-Treas., P. O. Drawer 2154, Spokane, Wash. The fifth annual meeting of the Columbia Local Section was held in Wallace, Idaho, November 19-20, 1915, with headquarters at the Samuel Hotel. The afternoon session scheduled for November 19, was adjourned to give the members an opportunity to hear the testimony in the case between the Alameda and Success mining. companies on trial in the Superior Court of Shoshone County. The Success Company offered some excellent mine models and maps and furnished some interesting testimony. In the evening a technical session was held at which Stanly A. Easton presided in the absence of the Chairman and Vice-Chairman of the Section. The following papers were read: Progress in Ore Dressing By D. W. Buckby,.. Mine Accounting for Small Mines, By J. E. Chapman. Zinc Smelting and Smelter Rates, By W. E. Henry.

Jan 2, 1916

By John C. LaScola, David M. Hyman, William P. Diamond

The U.S. Department of the Interior, Bureau of Mines, has established a computer-implemented coalbed methane data base containing data representing over 2,000 coal samples from approximately 250 coalbeds located in 17 States and one Canadian Province. Space for approximately 130 sample characteristics is reserved for each sample record and is divided for access efficiency into three separate physical files. A software package was written to provide a user-friendly environment in which the three files can be manipulated simultaneously. These files can be used interactively in DATATRIEVE 11, a commercially available sorting, retrieval, and report-writing software package or in any FORTRAN-compatible system for statistical analysis. The data base has been established for coalbed methane research in response to the health and safety needs of the mining industry. Possible applications of the data base include mine planning related to the occurrence of gas, as well as delineating areas of resource recovery and utilization.

Jan 1, 1983

By Vassiliki G. Stavropoulou

Although plane-strain is the preferred method of analysing many rock mecahnics problems, little is known about the behaviour of rock under this loading condition. A simple and inexpensive apparatus has been built for laboratory testing of rocks in plane-strain conditions. A thorough .investigation of the specimen geometry and the friction end effects showed that the results can be considered as reliable. The behaviour of a brittle sandstone in the simplest plane-strain condition [(03 = 0)] is significantly different than that of the uniaxial compression [(02 = U3 = 0)]. The plane-strain values of the Young's Modulus and the Poisson's Ratio are decreased in comparison to the corresponding uniaxial values. Dilatancy is also reduced in plane-strain, whereas the pre-failure brittleness of the rock increases. The most dramatic effect of the plane-strain condition is that on the strength of the sandstone, which increases by 49 per cent in comparison to its uniaxial compression value.

Jan 1, 1982

By N. Mao

This paper presents the results of a research effort to develop a technique for estimating in situ stresses by measuring stress-induced velocity anisotropy around a borehole. Relevant parameters required to make the estimate were identified and measured in the laboratory on a 35.6 cm (14.0 in) cube of Nugget sandstone with a 10.2 cm (4.0 in) diameter hole, under biaxial loading. Two pairs each of radially and tangentially polarized transducers were placed inside the hole with displacement directions either parallel or perpendicular to the principal stress directions. With this configuration, relative travel times were measured by both a pulsed phaselocked loop technique and a cross correlation of digitized waveforms. The biaxial velocity data were used to back-calculate the applied stress. The standard deviation of the differences between the calculated and applied stresses is 0.62 MPa (90 psi) for a stress level up to 8.63 MPa (1250 psi).

Jan 1, 1984

By Robert Sisselman

Cesium metal isn't on the government's list of priority materials for stockpiling, but it may be getting a big lift in that direction. Both the National Aeronautics and Space Administration (NASA) and the Atomic Energy Commission (AEC) have committed themselves to a long-range research program the outcome of which may boost annual domestic production to 37,000 lb by the year 2000. This would represent a sixfold increase in cesium consumption over the figures reported in 1968. To accomplish this dramatic increase, there must he some equally dramatic breakthroughs. Recent research efforts designed to shake the metal from its lethargic status in world markets have been concentrated in the areas of ion propulsion, thermionic power conversion and magnetohydrodynamic (MHD) power generation. The activities in these areas, all of which attempt to make use of cesium's unique properties, may lead to a practical method for converting nuclear energy into electricity and a cheaper and more effective alternative to liquid propellants used in long-range space flights.

Jan 1, 1971

By George Rice

SINCE my earliest recollection, the coal business has been in a state of unrest. It has always been a matter of bewilderment to the serious thinking, the instability of this most important industry; second only to agriculture in its effect on the great development of this country, and even more important in certain aspects, because without fuel railroads could not run, agriculture could not get its products to market, nor would the great manufacturing enterprises have been possible. I will not attempt to discuss the present serious -labor dispute or similar disagreements of the past; in the settlement of which more or less successful attempts have been made to equalize, temporarily at least, natural conditions through "joint agreement" as to prices paid labor; but will confine my views to the general underlying conditions of which the disputes are symptoms, and try to show how these must be remedied before there can be any hope of stabilizing conditions.

Jan 5, 1922

By C. T. Sheeran, J. C. Franklin

A commercially available microprocessor-based system capable of monitoring 512 channels has been interfaced with monitors for radon, working level, air velocity, and fan power. The basic system utilizes both 280 and 8080 microprocessors in a desktop central processing unit (CPU). CPU hardware includes keyboard, video display (CRT), and disk drive; a printer is used to keep permanent data records. Signals from all channels are transmitted to the computer in digital form where they are processed for alarm status. Software developed for the system allows for audiovisual alarms in the event of low and high readings, rate change, change of state, or communica- tion failure. Up to six channels can be continuously displayed on the CRT for current readings. Shift reports and trend logs may be generated to help the ventilation engineer determine average working levels and ventilation effectiveness. Additional software permits the operator to program command sequences which may be used to automatically restart fans after a power outage.

Jan 1, 1982

By Thomas Connolly

The Homestake Mine is situated in the northern portion of the Black Hills of South Dakota in a series of steeply dipping and highly folded Precambrian Rocks. The ore bodies are localized along plunging anticlinal and synclinal folds which are locally called "ledges." The gold bearing ore is confined mainly in the Homestake formation which is an iron-magnesium carbonate series of rocks. The individual ore bodies are pipe or lense-shaped zones which plunge 30º to 75º from the horizontal. These ore bodies range from 10 to 100 feet wide and 50 to 400 feet along the strike. Gold values are erratically distributed in a gangue consisting of cummingtonite schist, sideroplesite schist, quartz, pyrrhotite, arsenopyrite, chlorite schist and ankerite. Usually the ore bodies dip at 70° to 80º and often have folded shapes like "fish hooks" or "troughs." Ore grades must be determined by extensive sampling and all mining is based on assay control.

Jan 3, 1974

By S. D. Michaelson

Open pits and quarries are the major sources of all "hard rock" tonnage mined today. Normally, ore is fractured from the pit face by blasting and then truck-hauled to a primary crusher where pro- cessing begins; overburden (or waste) is generally truck-hauled from the pit to dump areas. Truck haulage of blasted ore and overburden accounts for some 25 to 50% of total mining costs in a typical open pit and commonly is the largest single cost factor. Obviously then, cost reduction efforts should properly focus on improving existing haulage systems and developing new breakthrough techniques for material transport. Continuous flow systems for large tonnages ordinarily will result in a lower cost than batch systems such as truck or rail haulage. Continuous flow with pipelines for liquids and slurries, or conveyors for medium to coarse dry materials (in the -8-in. range) are the economic answers for bulk materials handling over reasonable distances.

Jan 11, 1968

By S. A. Braley

DRAINAGE of acid mine water into surface streams of coal mining areas is one of the most serious problems of stream pollution, since there is no known method that completely prevents its forming and no economically feasible treatment after it has formed. The mine acid problem differs from other pollution hazards because acid production does not end with cessation of mining but actually becomes more evident when pumping is stopped. The acid problem in the Pennsylvania, Ohio, West Virginia, and Kentucky bituminous coal areas of the U. S. began with the first operation in 1761, and the volume of acid discharge today is largely the cumulative result of years of mining. Provided they lie above the drainage area, the oldest mines, now long abandoned, are almost without exception producing acid in the same manner as those now operating or recently abandoned. It is well to consider some of the many procedures that have been used to determine the composition

Jan 1, 1957

By Alvin W. Schillinger

During the past ten years, the Calumet Div. of Calumet & Hecla, Inc. has conducted extensive exploration and mining in the footwall of the Osceola amygdaloid lode in the native copper district in Michigan's Upper Peninsula. In an attempt to delineate more clearly the extent and nature of high-grade footwall copper mineralization, 876 diamond drill and long steel holes aggregating slightly more than 47,000 ft have thus far been drilled from the accessible hanging-wall workings. Early in this program it became obvious, through inspection of footwall workings in progress, that due to the erratic and bunchy occurrence of the native copper in the footwall zone, the exploration drilling was failing to outline completely the extent of the oreshoots. Early drilling results indicated isolated pockets of ore whereas in actual practice the footwall was found to be fairly thoroughly mineralized in shoots within the ore zone. Based on drill results only, the "success factor" (discovery ratio) was only 34%.

Jan 11, 1964

By W. M. Tuddenham, R. J. P. Lyon

In many areas surrounding the orebodies in mining districts rocks have been bleached and altered by the ore-forming solutions and have been oxidized during later weathering processes. A number of the rock-forming silic-ates have been broken down to clay, sericitic micas and chlorites have been developed, and pyrite may be found hundreds of feet outside the economic limits of the orebody. These halos of altered ground are prime targets used by geologists in many districts to delineate promising sites for drilling. Both in the field and in the laboratory it is often difficult to map these mineralogical changes in the halos in detail without numerous petrologic examinations. The secondary minerals are generally fine-grained, and since conversion of one mineral to another is often progressive, many alteration processes have not proceeded to completion (feldspars to clay to sericite mica). Qualitative detection of these minerals is difficult; quantitative determination is frequently impossible.

Jan 1, 1960

By O. Bilharz

The rules laid down by Peter von Rittinger in his classic Lehrbuch der Aufbereitungskunde (Berlin, 1867, p. 513) concerning the designing of dressing-works still possess authority for such works and their operation. Nevertheless, some modifications and additions suggested by practice may be of value at the present time. Rittinger says: "I. Choose the apparatus and machines which can be, under the existing con-' ditions, easily constructed and kept in running order!' This rule contemplates the construction of apparatus (mostly of wood) on the spot, with the command of good sbops and especially of good workmen in wood. But in many cases, particularly for the sake of a prompt supply, the construction of apparatus is now left to special manufactories, which pay more attention in the choice of materials to durability and strength than to easy manipulation and erection. Nevertheless, here,as in many other instances, simplicity of construction and solidity of execution are to be recommended. Especially important is the convenient and cheap replaceability of

Jan 1, 1894

By H. R. Steacy, A. H. Lang

Growth of general interest in uranium during the last ten years has been unparalleled in mining history, outranking the popular gold rushes and mining booms of bygone years. This is not surprising, considering the spectacular advances in nuclear research and the fact that a small amount of uranium can provide great quantities of energy for peaceful purposes. There are, however, a number of misconceptions and exaggerations regarding uranium. Many novices have highly exaggerated ideas of the ease of finding workable deposits, as opposed to mere occurrences, and reports of insignificant discoveries are sometimes given much publicity. Beginning about ten years ago mining for uranium has assumed a major place in Canadian and U. S. mineral industries. Uranium is now high on the list of metals produced in Canada. The gross value of uranium production in Canada in 1958, when additional plants now under construction are operating, will probably exceed 180 million dollars.

Jun 1, 1956

By Vernon Read

Among the technical problems in AEC's Project Plowshare is the necessity of determining the precise effects of nuclear blasts in all kinds of ground formations. This calls for extensive in-situ sampling with full core recovery. In the exploration drilling that often precedes a new test detonation, the AEC and its contractors have applied both novel and established sampling techniques in many new ways, giving improved core recovery and reduced costs in all subsurface sampling and testing. Unique among these new techniques is one that achieved full recovery and virtually undisturbed samples from near-surface layers of unconsolidated boulder-strewn alluvium. This approach involves a combination of oilfield and mining core drilling equipment. Oilfield heavy drill collars, rotary stabilizers and thick, vibration-reducing oil emulsion drilling mud were used in combination with the precise hydraulic feed control, fast (over 300 rpm) bit rotation, light drilling weight, hard rock core barrels and multi-step diamond bits that are common in mining industry diamond drilling.

Jan 8, 1963

By John R. Dyni

Colorado nahcolite deposits, estimated at 29 Gt, formed in an asymmetric permanent-lake basin whose waters were rich in algae and sulfate-reducing bacteria. Nahcolite (NaHCO3) occurs in oil shale of the Green River Formation (Eocene) as aggregates (62%), disseminated crystals (24%), and impure beds (13%). Because much of the nahcolite is nonbedded, it will be mined with oil shale and can be concentrated to marketable grade by crushing and screening. Impurities in nahcolite are kerogen, quartz, pyrite, and carbonate minerals. A promising new market for nahcolite is in the process of removal of sulfur dioxide from industrial stack gases. When heated, nahcolite reacts with sulfur dioxide to form sodium sulfate. Differences in thermally induced microporosity may explain why nahcolite is more reactive than trona, a Possible competitor with nahcolite for SO2 removal. Limited production of nahcolite at one or possibly two localities is expected in the next several years, but large-scale production is probably at least 10 years away.

Jan 1, 1982

By I. J. Demer, M. L. Holzworth, J. C. Kremer, P. A. Beck

For alloys which are in practice heat treated to obtain increased strength, such as steels, duralumin, copper-beryllium, and others, the treatment usually involves heating to a relatively high temperature. At such temperatures the grain size of the product is largely determined by grain growth. Even in metals and alloys annealed merely to relieve work hardening, recrystal-lization is generally followed by a certain amount of grain growth. Thus, effective grain size control, which is often of great practical importance in manufacturing processes, depends on the grain growth behavior of the material used. Despite its importance, grain growth has been the subject of few investigations of a fundamental nature. The term "grain growth" has been used to designate a group of related, but distinctly different, phenomena. The two most important and best known of this group are illustrated by the following example. Curve a in Fig I shows the increase of the average grain size of a copper-beryllium alloy, containing 2 pct Be and 0.15 pct Co, with increasing annealing temperature. The time of annealing was 2 hr. The grain size was quite uniform in all specimens. The results of a similar experiment with an alloy containing 2 pct Be and 0.31 pct Co are shown by curve b It is seen that for any annealing temperature below T, the grain size was smaller than. in the previous case. Grain growth became slower with the higher Co content. This "inhibiting" effect of the higher Co addition was associated with the appearance in the microstructure of fine, light blue particles of the CoBe phase. Up to temperature T, the structure of the inhibited alloy (curve b) was just as uniform as the structures represented by curve a. However, after annealing at T or at higher temperatures, the inhibited alloy showed some extremely large grains (much larger than the grain sizes developed by the uninhibited alloy with low Co content) mixed with the small grains according to curve b. The presence of these mixed or "duplex" structures is indicated in Fig I by the vertical lines branching off curve b. The type of grain growth occurring in uninhibited Cu-Be alloys (curve a) has been most frequently and best investigated in brass. This type has been designated as "normal grain growth,'' while the grain growth phenomena occurring in inhibited materials were, at times, referred to as "abnormal grain growth." However, since the latter term has been applied occasionally to the phenomenon of critical recrystallization, which also results in large grains although by an entirely different mechanism, in the present paper a different nomenclature has been adopted in order to avoid confusion. Typical of the grain growth in uninhibited metals and alloys is the continuous

Jan 1, 1949

As a result of Engineering Council's request to the Director of the Census, the National Service Committee has been successful in effecting a reclassification of engineers so that all technical men will be listed as such and they will be separate and distinct from the non-technical engi-neers. Thus, the next census will bring an enumeration of all technical engineers together as one unit under the main headings of civil, mech-anical, electrical and raining; architects also will be enumerated separately. This will enable the engineering profession, the Government or any other interested organization to know exactly how many technical men there are in the United States and in each state. The enumeration will also include non-technical engineers, except that there will be no such heading and in order to get the totals of non-technical men all of the various grades of this classification would have to be sorted out and added.

Jan 12, 1919

A three day international mining convention was held At the city hall of Nelson, B. C., June 19-21. It was held under the auspices of the Nelson-Slocan and British Columbia Mining Men's Club, the Northwest Mining Association of Spokane, the Kootenay Mine Owners' Association, assisted by the Spokane Chamber of Commerce, the Vancouver, Chamber of Mines, the City of Nelson, the Associated Boards of Trade of Eastern British Columbia and the Nelson Board of Trade. The technical program was in charge of Columbia Section, American Institute of Mining and Metallurgical Engineers and Western Branch and Kootenay-Boundary Branch, The Canadian Mining Institute. The first day was given over to the judging of mining exhibits and manufacturer's displays; the organization of a branch of the Canadian Mining Institute, and the reception of visitors from Spokane. On Friday afternoon a joint session of the Canadian Mining Institute and the American Institute of Mining and Metallurgical Engineers was held.

Jan 8, 1919

By John V. Beall

Dear J. B.: The recent cable I sent you for a transfer of $200,000 was the outcome of the diligence and perspicacity of our group which, as you know, is laboring under severe hardships here in Rondônia. I only mention the latter difficulties in passing because no reply has been received to our urgent appeal for money. As much as I detest appearing to plead for more attention than you feel called upon to pay to our forgotten mission, I can assure you that it would be in the best interest of the company for you to do so. The fact is, we have been able to outmaneuver the competition and have succeeded in securing pesquizas on some of the most promising cassiterite gravels. We have not been able, up to now, to do much bulk sampling (for lack of funds) but our preliminary panning shows great promise as you can see from the enclosed assay sheets.

Jan 1, 1971