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By Eldon Keith Stanek

This annual report deals with four distinct tasks related to research on the safety and reliability of mine electrical power systems. Task one is to develop tests and the associated instrumentation to detect incipient faults on a mine or any low-voltage power system. Task two is a dual effort related to the digital prediction of electrical transients on mine power systems and laboratory testing of transient suppression devices. Task three is also a dual effort. This task consists of both theoretical and laboratory work to assess both the reliability and the fail-safe characteristics of several items of protective equipment used in mine power systems. Task four consists of an effort to use programmable calculators and/or computer terminals to check overcurrent protective device coordination.

Jan 1, 1976

By Jack G. Quade

During the summer and fall of 1973 a series of Skylab and high-altitude aircraft overflights provided excellent hard-copy photographs of the Great Basin. These photographs, with a wide range of ground resolution were used by the NASA Project of the University of Nevada, Reno, to conduct specific geologic studies. The principal objectives of these studies were to: select individual areas covered by Skylab photography for detailed studies, develop mapping techniques using varied film-filter products with a wide range of ground resolution, compare the results of the mapping techniques to existing geologic maps at comparable scales, verify the results wherever possible by direct field observations. These studies were conducted by Jack Quade and Dennis Trexler and by graduates and undergraduates of the Reno campus under a contract with the Manned Spacecraft Center Houston, Texas.

Jan 1, 1976

By R. G. Bradburn

The events which led to computer control of the grinding circuit at Brenda Mines are described, beginning with mill operating philosophy. High production rates are encouraged so that, despite severe upstream disturbances, a manual control method to meet this philosophy had developed. Unfortunately, due to the time interval between manual control adjustments, losses in production resulted. An analog control method was devised and, although superior to manual control in some situations, was found to suffer from several practical limitations. The data logging capabilities of a control computer seemed warranted. Circuit test- work combined with an analysis of operating data showed that (1) metallurgical personnel, at times could increase production rates by as much as 10 percent over that achieved by grinding operators, (2) the chosen data base required an increase of 2 percent or more to be statistically significant and (3) for a 2 percent increase there would be a significant rate of return of investment in a computer installation, Consequently one grinding circuit was fully instrumented, and a rented control computer was installed by Brenda personnel. Prior to installation, Brenda metallurgical and instrumentation personnel were trained in the use of the computer. An experimental program was devised with short and long term objectives. The short term objective was to develop a practical control strategy which would yield immediate production improvement. This goal has been met as described in this paper. Statistically significant increases in excess of 2 percent have been established. Work is being completed for the permanent installation of computer control on all four grinding circuits at the present time. Long term objectives are (1) off line analysis of the circuit using mathematical models of process units, (2) on line experiments to study alternative contol tactics, and (3) possible expansion of computer facilities to the crushing plant.

Jan 1, 1976

By Raymond M. Stateham

Calculations based on data obtained from measurements of smoke from coal-fired powerplants predict that infrared imagers will be useful tools for smoke vision. Infrared imagers operating in the 3-to 5-um spectral region have been evaluated for this purpose. A mine opening 110 meters long was filled with smoke from burning coal, and two men, wearing breathing apparatuses, moved through the smoke to serve as targets. The men were detected and identified at 80 meters.

Jan 1, 1976

By William F. Butler, Mo-Hung Che

DEVELOPMENT OF MONEY AND MONEY STANDARDS This chapter is concerned with the rise, and then the decline and fall, of gold and silver as monetary metals. As a first step in tracing the history of this process, it is necessary to consider the nature of money, and the manner in which different forms of money have developed over the centuries. The origins of money go back into deepest antiquity. Once men ceased to be pure nomads and entered into even a rudimentary form of society such as clans or tribes, money had to be invented The first step was barter as farmers or hunters swapped their surplus products for things produced by artisans such as shoes, clothing, and simple tools. But such barter trading is inconvenient even in primative societies It is difficult to match up buyer and seller at any point in time There are problems in arriving at viable and acceptable terms of exchange. The accumulation of savings-wealth-is complicated. No one can be sure that a pile of furs, or wheat, or certainly fish or game can be used in the future to trade for other goods or services. So even prehistoric man saw the need for money. There was a need first for something to serve as a medium of exchange This was an essential first step in the process of specialization-or the division of labor. A farmer, a hunter, or a shoemaker could only devote his full efforts to his trade if he could be sure that he could exchange his surplus production for the other things he needed for existence. This required a medium of exchange-a form of money which would be broadly acceptable. Money was needed for two other reasons Some system of market prices was essential to facilitate the exchange of goods and services. This required some form of common denominator-some standard of value-to govern the exchange process. And there was also need for something to serve as a store of value, a place to put any excess production (savings) with the assurance that it can be used in the future to acquire a general range of goods and services. As a result, money, in one form or another, developed at a very early state in civilization. Yet the centuries have been marked by a search for a form of money which will possess in full measure all of the attributes in money-a reliable and universally acceptable medium of exchange, standard of value, and store of value. -A wide variety of things have been used as money at one time or another: shells, beads, stones, feather, metals, and even the teeth of sharks and dogs. Some of these things were obviously of little or no practical value. They were used because people had confidence in their continued acceptance as a medium of exchange. As the world evolved and as trading ex-

Jan 1, 1976

By R. H. Thorpe

In the earliest days of mining coal the obvious method was by bord and pillar working. Longwall in Britain developed from this as an expedient to overcome bottlenecks arising from ? 1) increasing depth of seams causing roof control difficulties; and 2) ventilation problems. This system became almost universal particularly in the thicker seams, where faces of up to one mile in length were not uncommon. Coal getting in these faces was usually by pick and shovel, filled into small waggons of up to 15 cwts capacity. These waggons ran on rails laid alongside the coal face and were often taken away from the face to the main haulage roads by horses. The roof was supported by rigid props and the wastes were normally controlled by strip packing. This system of mining was very flexible and worked well down to sections of about 3'6"

Jan 1, 1976

Since the discovery of coal of the Southern coalfield (Illawarra 1797, Burragorang 1806) coal mining has grown progressively to the thriving industry of today. Early shallow escarpment mining required no serious access development, but with extension of mining to further and deeper areas, sinking became necess- ary. Now, with 17 major shafts and 7 decline drifts in current use, new mining activities involve several current sinking and drifting projects, with more in prospect. Conventional sinking and drifting, using blasting and mucking techniques proven in recent years are normally in use, with attempts, recent and current to accelerate advances by boring techniques. With export and to less extent local market unpredictability, it is vital to produce mine establishment times to allow advantage to be taken of market upswings and there is great need for research and improvement of mine access construction as the major aspect of establish- ment.

Jan 1, 1976

By Edward A. McClatchie

A methane monitor that complies with 30CFR75.313 has been designed and fabricated using a novel pressure modulated infrared absorption technique. The methane monitor met or exceeded in performance all of its target specifications. The monitor was operated continuously during production mining for the entire duration (45 days) of the in-mine test; no failures occurred during the test. The monitor was regularly checked with calibration gas and no shifts in calibration were found during the in-mine test. Operating principles, performance data and electrical schematics are included in the report.

Jan 1, 1976

By J. D. Wright

INTRODUCTION The Endako deposit was first explored in 1926, but development waited until the early nineteen sixties. It first came under the control of Placer Development in 1963, and early in 1964 a decision to bring it into production was reached. The deposit is located near the geographic center of British Columbia, and is served by an east-west communication system including a paved highway, mainline railway and good telephone, teletype, and computer facilities. The plant area is shown in Figure 1. The operation is known as the Endako Mines Division of Canex Placer Limited of Vancouver. First production was achieved in June, 1965, at a nominal rate of 10,000 tons per day, but it soon was closer to 15,000 tons per day. In 1967, two new grinding and flotation, sections brought capacity to the present rate of approximately 27,000 tons per day. With mill heads of around 0.15 percent MoS2, production is about 14,000,000 pounds of molybdenum per year. A flowsheet of the operation is given in Figure 2. A legend for this flowsheet is given in Table 1. Published ore reserves are estimated at 214,500,000 tons at an average grade of 0.143 percent MoS2. PRIMARY CRUSHING The 85 or 100-ton haulage trucks dump over a grizzly into a 42 inch x 65 inch C.A.C. (Canadian Allis Chalmers) gyratory crusher. The

Jan 1, 1976

By James L. Ash

This report contains the results of a technical and economic evaluation of conceptual systems for the underground mining, rubblization; and in situ retorting of deep oil shale deposits. Study efforts were first directed towards evaluation of the applicable geology, associated minerals, rock mechanics, in situ retorting, access mining, ventilation, rubblization, safety, and environmental impact factors. Conceptual systems were synthesized and then evaluated against these factors from both a technical and limited economic viewpoint. The results of these evaluations were then analyzed 'and, based upon this analysis, the following two systems were selected for further study: System II: Room and Pillar-Vertical Drill and Blast System IV: Tunnel Boring-Horizontal Ring Drill and Blast Due to the large number of variables to be considered, a computer program was developed and utilized to provide data for the cost trade-off studies and economic analysis. Results of the early computer runs indicated the value of the tool available in the computer program and led to an extension in the contract to determine the sensitivity of the systems to several of the more apparent significant variables. These results in turn led to a refinement in the design assumptions and a better understanding of the technical and economic options available to an owner-operator of a Vertical Modified In Situ Shale Oil Extraction System. This report is submitted in fulfillment of the requirements of Contract Number S0241073 by Fenix & Scisson, Inc. to the Denver Research Center, United States Department of the Interior, Bureau of Mines. Work was completed as of November, 1976.

Jan 1, 1976

By P. A. Lawless

The objective of the research performed A for the Bureau of Mines on this contract was to develop a portable instrument for the detection of carbon monoxide (CO) in a mine environment. The desired characteristics were sensitivity and specificity for CO with a stable calibration. The sensor of the instrument was to be of metal oxide composition, requiring low power for compatibility with the types of batteries presently used in personal equipment in mines. The solid state design was also desired for ruggedness and small size. A key design feature of the instrument was to be provided by adherence to the intrinsic safety design requirements for electrical equipments operated in potentially exposive mine atmosphere. The Research Triangle Institute has prior experience in developing a solid state oxygen sensor using a thin film of zinc-oxide (Ref. 1) and experience in fabricating thin film devices. Solid state sensors utilized by other workers (Refs. 2, 3, 4, 5, 6) have included metal and semiconductor films and crystals of materials like carbon and aluminum oxide for the measurement of water vapor in the air and have relied upon measuring resistance and capacitance changes in the sensor in response to adsorbed vapors or gases. Since the effect of carbon monoxide in changing the resistance of various materials such as molybdenum, platinum, and zinc oxide had been reported (Refs. 7, 8, 9, 10), the requirements appeared to be realisable, although it was recognized even at the inception of the work that specificity to carbon monoxide might require the incorporation of more than one sensor.

Jan 1, 1976

By D. D. Hamilton

The ISMS program provided for the development and demonstration of equipment modifications in both conventional and continuous coal mining systems. This report describes activities during the demonstration of the continuous equipment and includes machine performance, results of data gathering, system evaluation, and recommendations for implementing improvements.

Jan 1, 1976

By Anthony E. Szczuka

The purpose of this design note is to document the data that has been received from manufacturers, coal companies, training centers, government agencies, etc., that pertains to the completion of the Concept Feasibility Study For Training Equipment Designed to Improve Coal Productivity. Revision A documents additional data that has been received. ACKNOWLEDGEMENTS We wish to express our appreciation to the companies, mines, government agencies, unions, and contractor agencies listed herein that furnished the documented data. In most cases, it was furnished willingly and free of charge. In the few cases where the data was purchased, MDEC IRAD funds were used.

Jan 1, 1976

VOLUME II Volume II, in conjunction with Volume I, is a general guide to the selection of cost-effective methods of site data acquisition in all geologic environmental, and socio-political circumstances. The judgement of a generalist or trained specialist must be relied upon in the final analysis to design the optimum program for a specific site.

Jan 1, 1976

Under contract from U. S. Bureau of Mines, Harza Engineering Company in cooperation with Eastern Associated Coal Corporation, conducted a ground control study of two mechanized longwall panels at the Federal Number 2 Mine. The mine is located in Northern West Virginia, and the coal is mined from the Pittsburgh Coal Seam. The prime objective of the study was to collect data which will aid in the proper selection of the longwall supports system and to control the entry caving problem. Instruments installed in the mine were borehole pressure cells, convergence recorders, roof sag recorders, horizontal roof strain indicators, differential floor movement systems, and lateral roof and floor movement systems. Instruments installed on the surface, above the instrumented longwall panels, consisted of slope indicator system, vertical bed settlement probe system and shear displacement detecting system. A comprehensive surface subsidence study was conducted in conjunction with the instrumentation. In addition to the instrumentation and monitoring, special tests were conducted to determine the bearing capacity of the roof and floor rocks, in situ modulus of coal, roof and floor rocks, and response of borehole pressure cells to ground stress. Cores of coal measure rocks were collected for the physical property tests. Face observations were made to detect various roof behavior parameters under the different jack setting pressures. This report essentially describes the instrumentation work, special tests and presents the data collected.

Jan 1, 1976

By D. O. Hamiltion

The ISMS program provided for the development and demonstration of equipment modifications in both conventional and continuous coal mining systems. This report describes activities during the demonstration of the conventional equipment and includes machine performance, results of data gathering, system evaluation, and recommendations for implementing improvements.

Jan 1, 1976

By Carl R. Peterson

[In lTI n,v und I'gr'oun nllnin~ Opt'I'ali n' the high . t cost is the loading and I 3ulage of t tln-of -D"'line ot'. 01' hauling costs can be r duced signifi-cant\v with the us ~ (r \) >It corn'e)'OI' " a COnlTllOn pl'acti c i.n coal and other s 0 t'L rn I n r' a l III i, n e , '. Jf 0 vel s i z ' () f' e can bee 1 i 11.11 tl ate I rH'i 0 I' lO C n v e . in g, ]

Jan 1, 1976

This report, authorized by a subcontract with the Crouse-Hinds Company per Section 1.1.3b of Contract Number H0220065 Amendment Number Six, and the consent of the Contracting Officer, documents the results of an investigation to develop solid state ballasts for Lucalox high pressure sodium lamps. The ballasts were to be used in the modified and new portable and machine-mounted lighting systems designed by the Crouse-Hinds Company, per Tasks I through IV of Contract No. H0220065.

Jan 1, 1976

By John C. Cook

Channel sand bodies ("wants" or "cutouts") are deposits of barren, hard sediments which interrupt production and pose safety hazards when encountered in underground coal mining. To locate these costly impediments to mining in advance, from the surface of the ground, the seismic reflection method is recommended. High-resolution (high frequency) techniques for shallow seismic exploration of coal beds have been worked out and are reported here, including a field example. Newly-developed high-frequency, digital recording equipment was used, together with light-weight shot-drilling equipment and a variety of down-hole seismic impulse sources. Techniques for rapid but complete coverage of a coal prospect area with a crew of 2 to 6 men n 2 or 3 vehicles are described in detail.

Jan 1, 1976

By Wesley G. Holtz

A project to demonstrate the feasibility of retorting oil shale by the Paraho vertical retort process was carried out at Anvil Points, Colorado during 1974 to 1976. As a part of the demonstration project, laboratory and field tests were performed to determine the physical and chemical properties of the retorted shale for use in the development of eventual full-scale disposal plans. The material which exits from the Paraho retort is classified as a non-plastic silty gravel by the Unified Soil Classification System. The particles have an apparent specific gravity averaging near 2.60 and a mass specific gravity averaging near 2.00. The material can be compacted by normal laboratory and field construction methods to about 90 to 100 pounds per cubic foot dry density depending upon the degree of compactive effort applied. The addition of moisture does not improve compactibility appreciably. When high compactive effort is applied the retorted shale is classed as impervious to water flow. The compacted retorted shale exhibits shear strengths in the same order as those observed for silty gravel soils. If the compacted material is cured (long tune simulation testing) prior to strength testing considerable strength gain can be obtained from cementing action. The amount of cementing developed is dependent upon heat treatment and other operating modes of the retort.

Jan 1, 1976