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By Oliver Bowles

Under a cooperative agreement between the Bureau of Mines, the United States Geological Survey, and the United States Bureau of Standards, a study of the stone-quarrying industries of the country was begun in 1914. The results of investigations made have been published from time to time.1 During the World War the Bureau of Mines centered its attention on problems relating to national defense, and detailed studies of stone-quarry problems were not undertaken except for an investigation of labor saving at limestone quarries, reported in Technical Paper 203, which related to a question of military importance. Since the return of peace, the high cost of materials and labor has made more imperative than in prewar times the conduct of investigations for aiding the quarrying industries in every way possible to adopt more economical methods and to utilize the most efficient labor-saving equipment. The publications already issued have had a wide demand, and in the interest of the quarry industries the bureau proposes to issue additions to the series as rapidly as funds are available. In an endeavor to promote economy and the reduction of waste in the slate industry, a study of slate quarrying was begun in 1920 and covered a period of about two years. Sixty-five active quarries were visited, and a detailed study made of all problems bearing on their successful operation. Field study was supplemented by a study of all information available in books or published articles on slate quarrying.

Jan 1, 1922

By Louis A. Panek, John A. Stock

A flat slot is created in rock to cause stress relief effects in a pair of hydraulic borehole pressure cells (previously installed in drill holes above and below the slot ) , which act as sensing devices . This relief is annulled by repressuring the slot by means of a flat hydraulic cell . The slot pressure at annulment is taken to be the existing ground stress at right angles to the plane of the slot . A number of trial installations in the rib of a mine drift showed that for a valid determination of ground stress the sensing devices that respond to relief and repressuring must be within a specified zone close to the pressure transmitter ; otherwise the indicated ground stress may be excessive . By using an additional pair of borehole pressure cells , installed a few feet away , the existing rock stress can be redetermined at intervals , irrespective of a change of stress intensity subsequent to the initial installation . Based on these findings , equipment and procedures have been developed that make possible the installation and operation of a permanent rock stress monitoring station for observing mining - induced stress changes . The station consists of a 12 - in - wide hydraulic pressure cell cemented in a flat slot and four 2- by 8 - in flat hydraulic pressure cells in nearby drill holes . All drilling for the installation can be done with an air leg drill and conventional bits . Once the installation is completed , all required information is obtained by Bourdon pressure gage readings . The apparatus is simple , relatively inexpensive , and reliable under operating conditions in a wet mine . Unlike most methods of rock stress determination , this scheme permits periodic remeasurement of absolute rock pressure over several years , without additional drilling or instrumentation . Similar to other flat slot procedures , stress measurements are obtained without making auxiliary tests to determine elastic

Jan 1, 1964

By James R. Aggson

This Bureau of Mines report describes floor heave ground control problems that have been encountered in a new underground coal mine in West Virginia. Previous experience in the coal seam, the results of physical property investigations, and in situ rock stress determinations are discussed. The apparent cause of the ground control problems is the existence of a high, biaxial, horizontal stress field coupled with a floor member that has time-dependent deformation characteristics, A theoretical analysis of the failure process is developed. The analysis is assisted by finite element techniques. Mine design recommendations based on this analysis are presented.

Jan 1, 1978

By Gary A. Kingston

Rolled steel, steel forgings, and steel castings in the Pacific Northwest (Washington and Oregon) are produced principally in the Seattle, Wash., and Portland, Oreg., metropolitan areas. Steel-mill products are rolled from carbon and some alloy &eels by three companies into shapes such as reinforcing bar, rods, rounds, squares, flats, and hot-rolled strips; structural shapes, - such as angles, channels, and I-beams, also are rolled. Carbon and alloy steel ingots are poured and forged at a Seattle plant into ship shafting, drive shafts, billets, slabs, bars, rings, hooks, and other items. Static, shell, investment, and centrifugal castings are produced at 19 steel foundries in a wide range of steel specifications. All Pacific Northwest steel output is based on remelting steel scrap. Local iron ore might be used in the future to supplement steel scrap as a metal source. Ore reduction would probably be achieved by methods other than the blast furnace. Current melt-shop practice and problems are basically the same in Pacific Northwest steel plants as in cold-melt shops in other parts of the country. Quality steel production is receiving more emphasis in this region with the installation of modern analytical equipment and vacuum pouring and melting facilities.

Jan 1, 1962

By Curtis H. Elder

In studies conducted by the Bureau of Mines, two test areas were hydraulically stimulated and exposed by mining: One in the Pittsburgh coalbed at the Vesta No. 5 mine, Washington County, Pa.; and one in the Illinois No. 6 coalbed at the Inland mine, Jefferson County, Ill. Induced fractures were contained totally within the coalbed with no adverse effect on the stability of associated rock strata. Induced fractures were vertical and were propagated normal to the direction of least residual tectonic stress. Gas production was increased fivefold to twentyfold by hydraulic stimulation.

Jan 1, 1977

By Oliver Bowles

The manufacture of lime is one of the oldest industries. Plants are distributed widely and furnish an essential raw material for numerous industries. The use of lime by the building trades, in agriculture, and in hundreds of manufacturing and chemical processes has created demands for a large production and has necessitated exhaustive research on methods of manufacture and uses. The bibliography of lime is an extensive one, but for the most part each publication has dealt with only certain operations. The purpose of this paper is to present a general picture of the industry as a whole. The abundant literature has been abstracted and quoted freely, and the National Lime Association has rendered valuable assistance in furnishing data for certain sections. Publications containing more detailed information on the various branches of the industry are referred to in the footnotes and in the bibliography.

Jan 1, 1936

By Paul C. Hyndman

No minerals have been produced from the McGraw Creek RARE II area. During the 1982 U.S. Bureau of Mines study, there were no active mines in the area. Limestone occurrences (fig. 1, no. 2), four copper prospects (fig. 1, no. 1, 4, 5, 6), and a prospect with no significant mineral values (fig. 1, no. 3) were examined. A moderate potential for high-calcium limestone resources was estimated between ocurrences within the study area near McGraw and Spring Creeks (fig. 1, no. 2). There is low potential for copper resources at the Argenta Prospect (fig. 1., no. 1) in the study area, and the McDougall Prospect adjacent to the area.

Jan 1, 1983

By N. A. Pace

This is one of a series of papers being published by the Federal Bureau of Mines for the dissemination of information on methods and practices used in the mining and preparation of crushed stone for market requirements. Performance in terms of units of work or tons produced per machine and per operator man-hour are given whenever that information is available. Direct operating costs are useful for comparing different methods, and are, therefore, included if possible. In addition to the factual description of equipment and methods used, it is desirable to discuss the engineering reasons for the choices that have been made. This paper is particularly concerned with the opertions at the Columbia plant of Palmetto Quarries Co. of Columbia, S.C. The plant is about one-half mile east of the Congaree River and adjacent to the southwest corner of the city of Columbia. Rail access is by the Atlantic Coast Line Railroad, and by a spur strack of the Seaboard Airline Railroad.

Jan 1, 1962

By A. J. Forney

The hot-gas-recycle process, for the hydrogenation of carbon monoxide, was investigated in a 12-inch-diameter reactor. Initially because the distribution of gas was poor, hotspots developed in the catalyst bed. After the velocity profile of the gas flowing through the bed was studied, the method of packing the catalyst was altered. Because this change improved the distribution of gas, temperature control was excellent. The l2-inch-diameter reactor was operated successfully in the synthesis of gaseous and liquid fuels. When high-Btu gas was synthesized in two stages, parallel-plate assemblies of Raney nickel were almost as active as granular Raney nickel in the second reactor. The pressure drop through the second reactor, however, was reduced 90 percent by the use of these assemblies.

Jan 1, 1962

By J. H. Nixon

A three phase program evaluated commercial proximity warning devices, developed and designed a microprocessor-based electrostatic field measurement instrument, and utilized this instrument to investigate the electro-static fields about power lines. The Phase I program consisted of test and evaluation of these commercially available proximity devices. The evaluation results were reported in the Phase I report entitled ?Evaluation of Proximity Warning Devices? dated 22 February 1980. The Phase II program resulted in the design and development of a microprocessor-based Distributed Sensor A.C. Electrometer which measures the electrostatic field present at 17 discrete locations along a crane boom. Operator control of the measurement system allows simultaneous electric field measurements from 17 probes, print out of the electric fields measured, and data archiving on magnetic tape for post measurement analysis. Under the Phase III program, electrostatic fields around a crane boom were measured by the instrument at 17 high voltage power lines of various voltages and geometries. The electric field data was processed and plotted versus boom distance from the power line. Analysis of the electric field data indicate that the distances at which a single sensor alarm will activate, vary by a factor of 3 to 1. This is due primarily to variations in boom orientation. The results also indicate that in the case of multiple power lines, a single electrostatic field sensor cannot reliably be used to determine the distance from a power line.

Jan 1, 1982

These proceedings consist of papers presented at Bureau of Mines Technology Transfer Seminars in December 1983 for the purpose of disseminating recent advances in mining technology in the area of mine ground control. The Bureau of Mines conducts several of these seminars each year in order to bring the latest results of Bureau research to the attention of the mining industry as quickly as possible.

Jan 1, 1984

By F. J. Prokoski

The COALSTAR Project, which operated from November 1981 to December 1982, was a research and development project aimed at providing a reliable and inexpensive means of monitoring various waste site conditions via the GOES satellite system. The GOES system provides data transfer from unattended isolated sites where neither power nor telephone lines exist. The reliability and resolution of the data received while using the satellite link were excellent; however, the site instrumentation gave considerable trouble. The disastrous failure of a large coal waste embankment in 1972 led the Bureau of Mines to undertake a comprehensive program to reduce the likelihood of such an occurence again. Part of this program involved the installation of instruments to monitor the stability of a specially-selected embankment operated by Armco Incorporated near Montcoal, West Virginia. Initially, the instruments were monitored by normal telephone lines and used normal commercial power from the local utility. The project described here was initiated to replace this monitoring system with an unmanned, solar-powered data collection system which transmitted data via satellite to a central computer facility. The satellite data network is the National Earth Satellite Service of the National Oceanic and Atmospheric Administration.

Jan 1, 1984

By Maria I. De Rosa

High temperatures encountered by mine rescue teams during emergency situations may cause severe physiological strain, hindering the men from carrying out rescue and recovery missions. A prototype ice-cooling garment (ICG) was developed by the Bureau of Mines to alleviate physiological strain due to heat stress. The effectiveness of the garment was tested with acclimatized and unacclimatized subjects at a typical work rate (1,200 Btu/hr) expected during rescue operations and at various hot environments (97° to 113° F dry bulb and 80° to 89° F wet bulb). During exposures with the ice cooling garment, the subjects were able to maintain a safe deep body temperature of 100.4° F or below Without the garment, the deep body temperature rose beyond values of 100.4° F, a condition considered unsafe for continuous work in hot conditions. Both heart rate and skin temperature values were lower while wearing the ICG. Subjective observation also indicated a marked benefit by wearing the ICG.

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 S. H. E. Phillips

This report describes the initial feasibility, the development and the field demonstration of a system for shaft sinking employing a high energy mechanical impact rock breaker and a compatible muck disposal system. The increased shaft sinking rates, decreased costs and improved safety conditions obtainable by the elimination of the less efficient conventional drill-blast-muck cycles are discussed. Four shaft sinking concepts utilizing the impact rock breaker in various shaft configurations are developed and the field demonstration in a rectangular shaft is described. The progress achieved, the problems and their remedies and the proposed modifications to improve the machine are described.

Jan 1, 1978

By Sam S. Taylor

Subsurface disposal of oil-field brines was practiced in Oklahoma on a limited scale as early as 1925. The technique of subsurface injection has been improved immensely and has been applied with varying success in many oil-producing areas in Oklahoma, and elsewhere. This method of disposal, however, is only one of several methods available to operators of oil-producing properties, but, in contrast with usual methods of handling brines on the surface it eliminates the damaging effect of mineralized water on fresh-water supplies, vegetation, and aquatic and other animal life. Other methods of brine disposal approved by regulatory agencies in some States include (1) impounding in impervious ponds and solar evaporation, (2) controlled diversion into surface waters, and (3) recovery of the mineral salts of the brine. In most States where oil is produced regulatory bodies authorize the use of one or more of these methods of brine disposal. In Oklahoma, for example, the .Oklahoma Planning and Resources Board of the Conservation Commission has been authorized4/ to adopt whatever methods or means may be necessary to prevent contamination by mineralization of all potable waters within the State.

Jan 1, 1942

By William H. Holley

Thirteen additional preservative/fire retardant systems were applied to Ponderosa pine and evaluated for flammability both before and after water leaching. The more promising four systems were given a thorough evaluation for flame spread, toxic gas and smoke density levels, resistance to decay, and compressive strength. The most promising system on the basis of history of usage in the mine, ease of application and low cost as well as overall performance is the Fyreprufe/ACC Albi 107A/ 144 combination. A survey of inspection tools and instruments, identified equipment which could be assembled into an inspection kit for use in determining the extent of decay and/ or impregnant retention levels in mine timber. A literature search identified those high fire hazard areas found in a typical mine. Timber and other wooden structures used in such areas should be treated with an acceptable fire retardant system. A survey of insurance companies revealed that the use of such treated timber in the mines would probably have little or no impact on the rate structure.

Jan 1, 1980

By Harold E. Marr

A simple algorithm is presented for processing digitized X-ray spectra obtained with a Si(Li) or Ge(Li) semiconductor detector coupled to a multi- channel analyzer. The simplified least-squares procedure is used to smooth out the statistical fluctuations in the spectrum by repeatedly fitting a quad- ratic equation to a predetermined number of channels and performing a traveling smooth across the spectrum. A logarithmic transform is applied to the raw data to minimize the distortion of the gaussian-shaped peak profiles. The efficacy of the technique is evaluated by observing the distortion of several gaussian-shaped peaks that have been subjected to the smoothing operation. The locations of maximums and minimums in the spectrum are predicted in the process as well as the values of the peak heights. The convolution integers from a least-squares fit of a quadratic equation are calculated as part of a FORTRAN subroutine. The building-block approach to computer programing in a small laboratory is discussed.

Jan 1, 1972

By Stephen Gerard Sawyer

This report presents a Fortran IV computer program for the structural analysis of space-frame protective canopies used in underground mines to protect equipment operators from falls of roof, face, or rib. This program entitled CANOPY permits rapid calculation of the elastic strength of a canopy for a variety of static loading conditions. Stresses in, and displacements of each structural member are computed and printed out. Additionally, identification of all members that have commenced yielding, weight of the canopy, total loads on the canopy, and maximum loads that the canopy can sustain elastically are output. Program description, input instructions, program listing, and two example problems are included.

Jan 1, 1972

By K. R. Dorman

To develop the potential of precast concrete sets as a support medium in underground mines, a three-piece precast concrete drift set was designed for a small opening and tested to destruction in an underground straining frame. Thirty-six tests were made with three sizes of members using three different loading conditions. In addition, 14 members were tested individually in the laboratory. Test results are compared with theoretical calculations. A cost comparison shows the use of concrete sets would be advantageous where conventional wooden timber requires excessive replacement.

Jan 1, 1968