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By Frank E. Cash

The compensation-insurance rates for quarrying in North Carolina are 11 times higher than for the State?s major industry, textiles. Some operators are willing to accept this as representing the ratio of existing hazards. This was not true of the management of the Southern Aggregates Corporation, and in 1935 it tools definite steps to correct the idea of its local officials and employees that loss of life and limb in quarries is inevitable. ACKNOWLEDGMENTS The authors acknowledge gratefully the assistance and information concerning these operations furnished by H. M. Shaw, safety director (also secretary and treasurer), Southern Aggregates Corporation, Raleigh, N. C.; by the following superintendents: J. H. Rodgers, Blair Quarry, Blair, S. C.; J. D. Lane, Greystone and Rolesville Quarries, Henderson, N. C. ; J. H. Arthur, Guilquarry, Stokesdale, N. C.; J. H. Watkins, Rockton Quarry, Wendell, N. C.; P. A. Wellenborne, Reidsville Quarry, Reidsville, N. C.; and J. L. Kirchin, Woodleaf Quarry, Woodleaf, N. C.; by the various foremen at the plants, and by Murry Id. Grier, safety engineer, North Carolina Department of Labor, Asheville, N. C.

Jan 1, 1940

By Charles R. Harrison

The purpose of this study and resulting development of the training program, "Safety--Let's Make It Happen" was to determine the relation of concepts to the development of desired Health and Safety behavior. After extensive pre-contract study, it was hypothesized that improved acceptance and understanding of the Federal Coal Mine Health and Safety Act of 1969 could possibly contribute to the reduction of accidents. Second, in order for an individual to accept and understand the Act, he or she must have a working knowledge of its purposes and application. Third, acceptance and understanding of the Act, necessary to protect the individual from negligence, was imperative. Fourth, an actual operating company could provide the base in which to test these hypotheses in a meaningful manner and develop this type of training program. Six assumptions were agreed upon before embarking on this study and training program development. (1) In the cognitive process, a concept introduction into an individual's personality may result in a behavior quite different than if he or she had been exposed to a different concept.

Jan 1, 1977

By M. A. Mahtab

This report presents a new procedure for analyzing the orientations of rock fractures in an engineering site. This procedure, coded in a computer program, identifies clusters or groupings among the fracture orientations and calculates (1) the mean orientation of the fractures within each cluster and (2) the dispersion or scatter among these fracture orientations. Data points are represented by intersections of joint normals with the upper hemisphere, which is divided into 100 equal-area quadrilateral patches. The points in adjacent patches where the Poisson distribution test shows significant concentrations are assigned to a single cluster. For a cluster whose fracture orientations follow Arnold's hemispherical normal distribution, a confidence interval for the fracture orientation mean is calculated by applying Fisher's estimates. The technique is applied to the treatment of three examples.

Jan 1, 1972

By Jaffrey Y. Foley

Placer gold and platinum-group metals (PGM) In the Slate Creek area, northern Chistochina Mining District, are derived from silicified and carbonate-altered, Cretaceous-Tertiary (?) dikes and related mafic and ultramafic rocks. Gold In the placer deposits is also derived from Tertiary conglomerate and altered Jurassic-Cretaceous argilllte. The argilllte and Igneous bedrock sources show a unique Ag-Au-Cu-Hg-PGM association that Is attributed to a combination of magmatic, hydrothermal, and supergene processes. The bedrock and placer deposits contain a variety of gold silver-lead-copper and PGM alloys. The observed geochemical, mineralogic, and alteration features are consistent with current geological models for turbidite-hosted gold deposits. No economic gold or PGM lodes were Identified, but several areas warranting more detailed investigation were Identified. Conventional geochemical sampling and analysis of small sample splits weighing between 10 and 30 grams were shown to be unreliable as a consistent means of identifying gold- and PGM-bearing bedrock. Pan concentration of pulverized rock samples was shown to be a more effective, but still Imperfect means of Identifying gold and PGM source rocks. Geochemical data and mineralogic examination indicate that gold and PGM in potential lode sources are very finely and erratically disseminated, are chemically combined with other elements, and may not be entirely free-milling or amenable to simple gravity concentration.

Jan 1, 1990

By P. A. Hendricks

This U.S. Bureau of Mines (USBM) report identifies and evaluates factors responsible for metal/nonmetal (M/NM) underground mining accidents involving mobile equipment. Information regarding the occurrence and severity of the accidents, the type of equipment involved, the primary and contributing causes, and preventive measures is included. The goal of this report is to provide information that will aid mine operators and safety managers in the recognition of hazards associated with operating mobile mining equipment in an underground mining environment.

Jan 1, 1994

By R. R. Sayers

The contemplated use of dichloro-difluorco methane in domestic and commercial refrigerating appliances and in air-conditioning equipment for public buildings and possibly homes, brims attention to the health hazards involved in a wide potential exposure of the public to vapors of another new product, and for the first time to vapors of an organic fluorino compound. The objective in the development of this new refrigerant, however, has been the mitigation of health and explosion hazards in automatic refrigeration, and accordingly these factors have been given primary attention. Early in the development, the Bureau of Mines as requested to make a laboratory study of the toxicity and potential hazard, and it was ca the oasis of the results is of this work and the results of a preliminary investigation made in another laboratory6 that the compound has been selected for commercial use. The investigation conducted by the Bureau of Mines is still in progress, enough information has been obtained to indicate the order of the toxicity and the magnitude of the health hazards involved in the use of dichloro-difluoro methane as a refrigerant. The following is a summarized report of the work completed to date:

Jan 1, 1930

By Phillip R. Moyle

A basic precept in mineral exploration is that the best places to prospect are where minerals have already been found. The California desert has many old mining districts once thought to be "played out" that are currently producing more mineral wealth than at any time in the past. Because no "crystal ball" exists that will enable us to predict the Nation's future mineral needs, land management plans must be flexible enough to respond to these often unforeseen needs. MANAGEMENT ISSUES The California Desert Conservation Area (CDCA) (figure 1) encompasses 25 minion acres, nearly one-quarter of the total area of California. Passage of the Federal Land Policy and Management Act of 1976 (FLPMA) launched an intensive program by the Bureau of Land Management (BLM) to study this vast area. Painstaking scientific investigations were made of wildlife and plant populations, soil, air, and mineral resources, range use, and wilderness characteristics, among other environmental concerns.

Jan 1, 1992

By Thomas O. Llewellyn

This U.S. Bureau of Mines (US8M) report presents a concise review on sources, processes, supply, and historical use patterns of domestic cadmium. It also covers a preliminary estimated cadmium material balance for the year 1989.

Jan 1, 1992

By C. F. Jackson

This paper describing the mining practices at a mine in the Southeast Missouri district is one of a series being prepared by the Bureau of Mines on mining practices, methods, and costs in the various mining districts of the United States. The conditions, operating methods, and practice described in the following pages arc those obtaining at a property in the Southeastern Missouri lead belt, St. Francois County, Mo. This property is the eldest in the county and is a consolidation of a number of separate mines originally opened up as individual operations many years ago. Present-day operations have necessarily to be adapted to suit the older levels, stones, and pillars, and also the recovery of ore from worked over areas which was considered too low grade to mine in the earlier days constitutes a different problem than that of development and mining in virgin ground.

Jan 1, 1929

By F. G. Miller, H. C. Miller

Petroleum technologists and progressive operators constantly are striving to increase the percentage of oil that may to recovered from reservoir rocks through wells. The exhaustive studies that have been made of the function of natural as in the production of oil, for example, have aided operators greatly in increasing the quantity of oil recovered from reservoirs. Natural gas dissolved in and otherwise associated under pressure with oil in reservoir rocks, however, is not the only source of energy available for moving oil through sands to wells. In becoming "reservoir—energy conscious" engineers have learned that in many petroleum reservoirs the edgewater flanking the oil accumulation constitutes a potential source of energy capable, through proper control, of increasing oil—recovery efficiencies materially. No longer is the encroachment of water into the oil— and gas—filled tart of the reservoir considered as an evil to be combatted by devious methods but rather a natural consequence, incident to the withdrawal of nil and as from the wells, that may be used advantageously in lengthening the flowing life of wells and increasing the economic recovery of oil and gas.

Mar 1, 1938

By Richard C. Wang

The U.S. Bureau of Mines established a wire rope research laboratory to examine the factors that affect the safety and the useful life of wire rope. In the most recent work, two 32-mm 6x27H flattened strand ropes were degraded on a bending fatigue machine. The two tests were run at constant loads of 285 and 347 kN or safety factors of 2.5 and 2. Nondestructive and tensile strength tests were performed on samples of the ropes to determine the relationship between rope deterioration and rope breaking strength. Neither the area loss nor the number of broken wires measured from nondestructive tests could be used as clear indicators of the loss of strength. However, it was found from the tensile tests for both rope specimens that the strength loss was associated with the reduction of breaking strain. This suggests that measuring the strain of many short sections of a rope in the elastic region may locate the high stress sections and thus delermine the condition of the rope.

Jan 1, 2010

By Michael S. Miller

In 1986 and 1987, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied the nine separate parcels that comprise the 4,330-acre South Warner Contiguous Wilderness Study Area in order to evaluate their identified mineral resources. The nine parcels are along the east side of the South Warner Wilderness. They are, from north to south, the Granger, Milk, Cottonwood, Owl, Hornback, Eagle, Emerson, Barber, and Van Riper parcels. The Wilderness Study Area is underlain by basaltic, andesitic, and rhyolitic volcanic rocks and by sand and gravel deposits. Low-grade metamorphism is widespread in the volcanic rocks, with quartz, zeolites, datolite, chlorite, and calcite locally abundant in veins and amygdules. The rocks have been displaced by the mountain-front Surprise Valley fault and by crosscutting high-angle faults.

Jan 1, 1988

By A. R. T. Denues

"INTRODUCTION The orienting phases of the current investigation of cushioned blasting in the Explosives Division of the Bureau of Mines were indicated in a previous publication (5) 3/. Pertinent literature reviewed therein indicated a highly controversial field. This emphasized the need for experimental studies of many factors that affect the health and safety of miners and the efficiency of mining operations. Results of some orienting tests showed marked effects on practical hazards. Further, they emphasized the necessity and importance of the contemplated investigation. The scope and general plan of these practical inquiries into the safety of cushioned blasting were indicated.This investigation of cushioned blasting relates to the various means employed to reduce the intensity of application of energy from explosive actions in boreholes. It has been suggested (from p. 19 of reference 5) that the divisions of this work would correspond to the salient hazards affected by cushioned blasting. These include the ignition hazard, hazards from poisonous gases, and other practical hazards in the blasting technique. The ignition hazard was resolved into two components of approximately equal weight. These include studies of effects upon (1) the incendivity of blown-out shots and upon (2) the occurrence of such shots. Experimental studies of effects on the incendivity of blown-out shots were first undertaken. Questions of the best procedure for making these evaluations have been adduced, and the interpretation and utilization of the results of gallery testing seemed to require detailed attention; some preliminary general considerations of such testing were therefore necessary."

Jan 1, 1943

By R. G. Meara, O&apos

[P.F? bmit e-ninirq ir.3.l r;tq: in the Znited State :; was u~irlyortant p~ior to the Torld ;Jar, ?-.lt with the c~r,sxti~rl of imports d11rln.c thr World 'Jar tke Rmericnn mar~factu~er:. of 1itkopone mcl Sayiun c;~oai?als forced tile tl~veloor?.ent of domertic bar,i$e dqosit9. Pr%~~,n-ily bcca-lse of tho increasing dc.n;;nl'i for lit,hupone3 by the pr?i:~t, Tlocr-covcrin~;, ,md rt1tbe.r indl~stries, ~3c.vs1o~:rnc2t of cto~entic de~onits has cr~ntim~ed to c-cpand. 13 1914, the salnr! oC doxegtic c~l~.dt? t,m-it~ ;u~cr-~nteii. to 52,91? tons, in 1237 ???,1!.1 tons nmre so1.d; thc 12:t~r rcyrprcntcd 77 .E;T pmccnt of the tot,:rl, dr??;ectic and imortcd., haritd US~C in the Cnited State? di7rinz t,hat :.vXr. C,f +he total 193,3:& ton? coy.1~-ed in the United 4 Steter ir. 135, 3E.X percent v;as usec? as groi.z.ld ~rai.te? , "0.3 percent arr lithopone, and 17 .:A ].ercc?t in the rnx 11fact,ure of b;~riim chs:nicals ]

Jan 1, 1938

By R. G. Meara, O&apos

[P.F? bmit e-ninirq ir.3.l r;tq: in the Znited State :; was u~irlyortant p~ior to the Torld ;Jar, ?-.lt with the c~r,sxti~rl of imports d11rln.c thr World 'Jar tke Rmericnn mar~factu~er:. of 1itkopone mcl Sayiun c;~oai?als forced tile tl~veloor?.ent of domertic bar,i$e dqosit9. Pr%~~,n-ily bcca-lse of tho increasing dc.n;;nl'i for lit,hupone3 by the pr?i:~t, Tlocr-covcrin~;, ,md rt1tbe.r indl~stries, ~3c.vs1o~:rnc2t of cto~entic de~onits has cr~ntim~ed to c-cpand. 13 1914, the salnr! oC doxegtic c~l~.dt? t,m-it~ ;u~cr-~nteii. to 52,91? tons, in 1237 ???,1!.1 tons nmre so1.d; thc 12:t~r rcyrprcntcd 77 .E;T pmccnt of the tot,:rl, dr??;ectic and imortcd., haritd US~C in the Cnited State? di7rinz t,hat :.vXr. C,f +he total 193,3:& ton? coy.1~-ed in the United 4 Steter ir. 135, 3E.X percent v;as usec? as groi.z.ld ~rai.te? , "0.3 percent arr lithopone, and 17 .:A ].ercc?t in the rnx 11fact,ure of b;~riim chs:nicals . ]

Jan 1, 1938

By Robert M. Becker

This report (part 3 of a five-part series) presents computer programs for evaluating moments and moment relationships of the generalized probability distributions extended or developed in parts I and 2. The principal program is for evaluating the first three moments and moment relationships of the compound-multinomial distribution for finite as well as for infinite populations. This is the generalized distribution for sampling to some amount of items per sample. Another program is for evaluating the first four moments, the moments of the mean, and the moment relationships of the multinomial and generalized hypergeometric distributions. This is a general moment program in sampling to some number of items per sample or for sampling to some number of samples. This program will accept either ungrouped data, frequency data, or probability data.

Jan 1, 1965

By Theodore R. Jolley

The estimated recoverable reserves in the area in the vicinity of Eska 2 mine are, 699,300 tons in the Chapin and Emery bas of the Maitland group. Those recoverable reserves are in the area between the Eska fault zone and Jonesville fault and extend down dip from the outcrops. No reserves were developed by the Eska 2 entry or by drill hole 14-16 in the Eska fault zone. The small quantity of reserves in the vicinity of the Eska 2 mine is insufficient to justify development of a now, modern .nine in this area. The estimated recoverable reserves in the area east of aka Creek are 974,500 tons in the Eska, Shaw, and Martin beds of the Eska group. Most of those reserves occur in the south limb of the syncline. It will be necessary to practice subjacent mining methods to recover these reserves in the Eska group. The Eska bed developed by the diamond drilling in this area comprises coal end few thin partings. The Shaw and Martin beds comprise two bunches of coal separated by partings, and the product from full-bed mining will require thorough preparation.

Jan 1, 1952

By Eldon C. Pattee

THE BUREAU OF MINES began an investigation of tungsten resources of Montana in September 1953. This report presents information obtained from July 1955 to September 1957 on tungsten deposits in and near the Mount Torrey batholith. The batholith comprises part of the Pioneer Mountains of Beaverhead County in the southwest corner of Montana. Included in the report are assays and preliminary-examination data on 22 properties. Tungsten minerals are known to occur in 19 of the properties. The major producer is the Brown's Lake mine which has produced more than 625,000 tons of ore. Nearly all of the deposits are in the Lost Creek, Utopia, and Bald Mountain mining districts along the east and south margins of the Pioneer Mountains. The districts are less than 27 miles from Dillon, Mont.

Jan 1, 1960

By R. A. Beall

This bulletin reviews the historical background of the cold-mold arc-melting technology, with specific references to the development that led to homogeneous zirconium ingots. Descriptions are given of modern production arc-furnaces for vacuum melting of troth exotic and conventional metals. Besides zirconium, specific data are given for production of chromium, thorium, and copper. The development of the skull-casting technique for titanium is detailed, and the application of the technique to such refractory metals as molybdenum and tungsten is described. Factors of operation of the apparatus and furnace design are considered.

Jan 1, 1968

By Donald O. Capstick

A mineral resource evaluation of the Coyote-Southeast RARE II area (No. 5033) was performed jointly by the U.S. Bureau of Mines and the U.S. Geological Survey in 1981 for the U.S. Forest Service RARE II program. Bureau of Mines personnel conducted a mineral resource inventory of the study area's mines, prospects, claims, and mineralized outcrops. The study area's boundaries encompass 51,700 acres on the east flank of the Sierra Nevada and are within Inyo National Forest southeast of the city of Bishop in east-central California. Cretaceous granite underlies most of the area; the remainder of the rocks are metasedimentary. At the contact of the two, tactites formed at many places where carbonate rocks were present; replacement processes produced local scheelite (calcium tungstate) occurrences.

Jan 1, 1983