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By David E. Nicholson

This report investigates the mechanical behavior of fine soils in a lunar environment in engineering gravity-flow bins. The ultrahigh vacuum, absence of moisture, and a lunar gravity one-sixth that of earth gravity represents a unique environment, both advantageous and detrimental to these systems. On earth, moisture and gases contained in powder masses can be responsible for complex descriptions of gravity flow. Their absence appear to simplify the lunar soil behavior. However, simulation of the lunar gravity and vacuum complicates the development of experimental data for designing bins. The properties of a dry soil powder, its behavior under one-dimensional compression, and its torsional and direct shearing strength under earth atmosphere are described in part 1 of this paper. These properties provide the parameters for a finite-element analysis to optimize the design of bins, to be described by Dr. William Pariseau in part 2. Shear tests assess the failure criteria for the material. Compression tests provide modulus and (Ko) stress-ratio values from the loading portion of the compression cycle, duplicating the condition of a bin at rest with the discharge closed. During the unloading portion of the compression cycle (soil overconsolidated), the residual Ko values rise. It is postulated that this phenomenon creates a high-lateral stress in bins when they approach incipient flow. Assessment of the Ko value, overconsolidation ratio, and the void ratio state is proposed as a criterion to determine the flowability of powder.

Jan 1, 1971

By Floyd G. Anderson

A study was made of the effectiveness of dust-control methods being employed in connection with continuous-mining operations. Airborne dust exposures of workmen and dust loadings of return air were determined for six types of continuous-mining machines. The conditions required for control of dust exposure are summarized and include ventilation of the working face by an exhaust system. Return-air dust loadings ranging up to 13 pounds per hour are reported.

Jan 1, 1963

By Douglas F. Scott

This case study provides an example of how social marketing was applied to meet the needs of business customers. Federal regulations require that all companies develop a written program to track hazardous chemicals at their sites. The HazCom Writer, created by the National Institute for Occupational Safety and Health (NIOSH), is a software tool designed to help companies prepare their required Hazard Communications (HazCom) written plan and list all hazardous chemicals at the company's worksite. The social marketing goal was to provide a product for small- to medium-sized companies to use for federal HazCom rule compliance. The HazCom Wm'ter is a direct NIOSH response to customer and stakeholder needs (including the Mine Safety and Health Administration, the mining community, and Occupational Safety and Health Administration- regulated companies).

Jan 1, 2009

By P. B. Grote

The report is concerned with the issue of the possible transfer of U.S. and other developed country deep ocean mining (DOM) technologies to developing countries. This subject is one of several major issues in current UN Law of the Seas negotiations. As background to the subject, the report provides a detailed critique of the various terms and conditions pertaining to technology transfer in recent negotiating texts. It also provides a description of the relevant DOM technology, sources of innovation, and methods of proprietary protection. Functional requirements for viable technology transfer are developed and used as a basis for the definition of alternative levels of programs and implementation approaches, including required changes in the negotiating text. The consequences of these technology transfer options on the various parties are investigated.

Jan 1, 1978

By J. C. Gerdeen

It is of upmost importance to keep the size of the program to a minimum for the computer being used. One way is to reduce the size of the data bank by adjusting the large common array A in the main program (page, line 32) and the statement following the assignment of A. The current value of A is 35001 and is optimized for the UNIVAC computer with 5,000 words of useable storage. Another way to reduce the required storage is to overlay the program. That is, to have in the computer only the subroutines which are being used. In large finite element codes, overlays or segmentation of the program is a necessity. The code presented here has three levels of segments and are presented graphically in the tree in Figure D-1.

Jan 1, 1976

By H. H. Fields

The Bureau of Mines is in the process of degasifying a virgin area in northern West Virginia from the base of an 839-foot-deep vertical borehole¬. An in situ gas pressure hole 199 feet long, and seven degasification holes ranging in depth from 500 to 850 feet (average 618 feet) were drilled in an 8-foot-thick virgin Pittsburgh coalbed from the enlarged (14-foot-diameter) bottom of this borehole. The in situ pressure at the back end of the hole and the range of gas and water flows from degasification holes as they were completed and closed off were 203 psi, 79,000 to 257,000 cfd (average 160,000 cfd), and 5 to 8 gpm per hole (average 6.8 gpm), respectively. Twenty-four hours after the seven holes were connected through individual water traps to a common collector for natural venting of the gas through pipes to the atmos¬phere, the total gas and water flows and the in situ pressure dropped, respec¬tively, to 971,000 cfd, 1.3 gpm, and 18 psi. Eighty days later the correspond¬ing values dropped to 529,000 cfd, 0.50 gpm, and 13 psi. After 180 days of degasification, 91 million cubic feet of gas had been removed from the affected virgin area. This represents 60 to 70 percent of the gas calculated to be contained in the area of coal affected by the holes.

Jan 1, 1973

By W. M. Mark

This investigation was undertaken to develop methods to improve the quality of titanium sponge produced by the Bureau of Mines modification of the Kroll magnesium reduction process. Research revealed that by systematic elimination of detrimental impurities introduced with the raw materials and by improved handling and processing techniques, high-quality ductile titanium with a hardness of less than 110 B.h.n. (Brinell hardness number) can be produced consistently. This improvement was accomplished by helium (or argon) stripping of residual atmospheric and other dissolved gases from the titanic chloride, preliminary dehydration of crude titanium sponge, and careful regulation of the titanium tetrachloride (TiC14) feed rate to the reactors.

Jan 1, 1960

By Walter E. Lewis

The Fort Randall Reservoir project, on the Missouri River at Pickstown, S. Dak., was designed by the Corps of Engineers and is part of the Missouri River Basin Development Program. The location of the project with respect to adjacent features is shown' in figure 1. When the project is finished, it will include a large earthwork dam and 12 circular tunnels, 8 of which will be equipped for power and 4 for flood control. Various phases of the construction have been contracted to independent companies, and at present four companies are working on different phases of the project under a rigid time schedule. Western Contracting Corp. is the contractor on stage II, earthwork; Johnson-Winston Construction Co. is the contractor for construction of the intake towers at the upstream side of the dam; McCarthy Improvement Co. has the contract for the power house and the outlet works on the downstream side; and Silas Mason Co. has the contract for driving the power and flood-control tunnels. The latter two companies use the same roads for ingress and egress to their respective work areas and the same general waste dump area. Under such circumstances, it is necessary that each company stay on a time schedule in regular sequence to avoid interference with the other.

Jan 1, 1951

By Hanns J. Billmayer

This report, which covers the period from April 1975 to November 1975, describes the work performed in compliance with the requirements of Contract No. H0357091. The purpose of this contract was the development of protective canopy concepts applicable to rail haulage equipment used in underground coal mines.

Jan 1, 1976

By Howard M. Stainer

Published X-ray mass absorption coefficients were compiled and tabulated. These coefficients are required for various X-ray analytical techniques. Values obtained from 28 authors are listed for 87 elements with both experimental and calculated points included; the wavelengths range from 4.01 to 68 A. Representative graphs are presented for six elements (lithium, nitrogen, iron, silver, holmium, and uranium. A 37-item supplementary bibliography is also included.

Jan 1, 1963

By J. Patrick Ryan, Thor H. Kiilsgaard, Charles W. Merrill, E. T. McKnight

The U.S. Treasury stocks of silver have been reduced at such a rapid rate to meet industrial and coinage requirements that they face exhaustion in 3 or 4 years. Alleviation of the silver problem will require increasing supply or reduc ing demand. This paper examines poss ible long-range resource development and research programs and improved secondary recovery. The possible reduction or elimination of silver in coinage and development and introduction of substitutes in the arts and industry are also discussed.

Feb 1, 1965

The small-scale surface mining operation in northern regions is typically located in a remote, ungaged basin. With the recent increase in the economic potential of mining, the number of small operations is increasing. The year-to-year variability in precipitation in this region under study is of great concern to mine operators. Some years may yield only 5 to 6 inches of precipitation, while others may yield in excess of 15 inches. Such variability makes placer mining operations difficult to plan, since low water years may result in too little run-off for gravel washing and high water years may result in flooding of mining developments. There are no official streamfloaw records in many watersheds in the northern region containing placer mining claims. However, information from other streams permits calculation of an estimated discharge for a watershed under consideration using average flows per square mile of drainage. It is to be emphasized that these are average or expected figures in reality, one water year may be significantly wetter or drier than another. This high variability of annual precipitation is significant in relation to placer operations because of the large quantities of water required for this type of mining. Some operations can not operate in low water years. In the larger watersheds, operations may continue in low water years but at a slower pace because of longer water collecting times. The high variability of available run-off rakes placer mining in many parts of Alaska difficult to plan on a long range because of the unpredictability of water supplies.

Jan 1, 1985

1.0 Control House (DWG. NO. 56-401-G) - 1.1 Physical Description The Control House is a single story, 2728 square foot building with an adjacent transformer yard. A four foot overhang provides shade protection for the walls. The building is heated and air conditioned. The HVAC System has an elevated outside air intake and provides a positive pressure environment within the structure in order to prevent the infiltration of heavier-than-air, noxious gases. The materials of construction are as follows: Structure : Light-Gage Metal Framing Exterior Walls :Outside - Preformed, Metal Siding :Inside - Insulated Metal Liner Panels Interior Partitions :Gypsum Board over Light-Gage Metal Framing Roof :Insulated, Preformed Metal Panels Ceilings :Mechanical & Electrical Rooms - Exposed underside of Roof Panels Control Room, Lunch Room, Toilets, Entry - Suspended Acoustical Lay-In Tile Floors :Mechanical & Electrical Rooms - Concrete Slab on Grade Control Room, Lunch Room, Toilets, Entry - Resilient Tile Exterior Doorsand Windows :Preformed Metal Panel Manufacturer's Standard Units

Jan 1, 1979

By Larry Patts, Jon Hummer, Jim Noll, Aleksandar Bugarski1, George Schnakenberg, Steve Mischler, Mike Crum, Shawn Vanderslice, Rick Anderson

This study is organized under the auspices of the Metal/Nonmetal Diesel Partnership formed by the National Institute of Occupational Safety and Health (NIOSH), the National Mining Association (NMA), the National Stone Sand and Gravel Association (NSSGA), the United Steel Workers of America (USWA) and the MARG Diesel Coalition. The ultimate objective of the study is to reduce the exposure of underground miners to diesel particulate matter (DPM) and gases, and to help in fulfilling the partnership’s goal of identifying technically and economically feasible controls to curtail particulate matter emissions from existing and new diesel powered vehicles in underground metal and nonmetal mines. The majority of current knowledge on the performance of the diesel particulate filter (DPF) systems and other control technologies is based on studies done under laboratory conditions, the results then being applied the results to on-highway vehicles. According to the best knowledge of the authors, only two comprehensive studies that were conducted recently at Noranda’s Bathurst Mining and Smelting Mine and International Nickel Company’s Stobie Mine under the sponsorship of the Diesel Emissions Evaluation Program [McGinn 2001, Bugarski and Schnakenberg 2001, Bugarski and Schnakenberg 2002] offered some insight into the problems associated with the deployment of modern DPFs to underground mining vehicles. The U.S. mining industry has expressed concern that this rather limited knowledge base is not sufficient to help them comply with the rule limiting DPM exposure of underground metal and nonmetal miners [30 CFR 57.5060 2001]. The partnership agreed that a series of comprehensive field evaluations of DPFs in several underground mines was needed to determine their viability of DPF systems and establish confidence in their performance. The first in this series of studies was the one conducted in Stillwater Mining Company’s Nye Mine, Nye, Montana. This study was conducted in two phases. The objective of the first phase was to establish the effectiveness of the selected technologies in reducing diesel emissions by using an isolated zone methodology. The objective of the second phase was to assess the effectiveness of diesel particulate filters in controlling the exposure of underground miners in actual production scenarios. As part of the first phase of the study a series of tests were conducted at Nye Mine from May 19, 2003 until May 30, 2003. The results of Phase I of the study are presented in this report.

Jan 1, 2005

By F. S. Kendorski

This report presents the results of a program to improve, using existing and proven technology, unstable highwall conditions through better blasting practices in Appalachian strip coal mines. Better borehole blasting agent distribution and optimization of burden, spacing, and delay periods allowing satisfactory breakage with minimal backbreak were the objectives. At a selected field site, geologic conditions were closely examined with regard to joint orientation and spacing, and resulting slope stability considerations. A test series of eight blasts was completed and the resultant highwall monitored by repetitive photography. The study of drilling and blasting economics along with equipment performance led to an economic model of blast parameters and the identification of blast design cost benefits. The work demonstrated that small strip mining companies' are able to achieve a more stable highwall excavation utilizing presently available technology, equipment, and explosive products at improved operational cost and safety.

Jan 1, 1981

By Andrew K. C. Wong

Hydraulic transport has been considered as one of the most economical methods in transferring granular materials over relatively long distances. In the natural world, it is used to transport basic material required for the support of life; in industry, it is a method widely adopted for handling materials. But the phenomena of hydraulic transport has not yet been thoroughly understood. As most of them are conditioned by a number of hydraulic and mechanical parameters, of which the basic relationships are not fully known, the traditional approach in relating these parameters to the energy requirement is purely empirical in nature. Empirical formulas, such as that proposed by Durand, (1) only give satisfactory results over a selected range of (particle size)/(pipe diameter) ratios and slurry concentration. When the case is more complicated or when new situations arise, the empirical formulas fail to give good predictory results. In fact, most of these formulas are based upon dimensional analysis, where the underlying physical interaction is not explicitly considered. Apart from the loosely related, non-dimensional groups incorporated in the formulas, there is practically no analytical means for modifying the formula so as to enable it to cope with more complex real physical situations. Although it seems quite remote that a complete rigorous solution to this highly complex problem could be generated in the near future, it is generally recognized (2, 3) that research in this area should be directed to more comprehensive studies of the obscure phenomena. In fact, there are a good number of very basic problems such as the effects of gradation and concentration of particles upon

Jan 1, 1972

By T. Bajpayee, J. Ellenberger

Microseismic monitoring and evaluation is one aspect of the National Institute for Occupational Safety and Health (NIOSH) research program. Roof falls are often preceded by a period of elevated microseismic activity, but not all periods of elevated activity result in a roof fall, nor do all roof falls occur after some amount of elevated activity. The objective of this study is to review periods of elevated microseismic activity and determine whether fracture activity rate can be used to anticipate the initiation of roof falls. The study was carried out at an underground limestone mine where major roof falls are associated with excessive horizontal stress. The progression of roof falls was detected by the microseismic signature produced by the rock falling from the mine roof onto the mine floor, which is termed a roof fall impact event. A total of nine elevated fracture activity periods that resulted in seven major roof falls were examined. It was observed that elevated fracture activity preceded the initial roof fall impact event in three out of four major roof falls. The initial impact event was not identified for the remaining three roof falls. Fracture event rates were analyzed and a roof fall alarm trigger of five fracture events in a ten minute time period was established for this test case. The fall alarm trigger was tested against six of the elevated activity periods. Four roof falls occurred in the six periods of elevated activity, and two would have triggered the alarm before the roof fall occurred, while two false alarms were generated. The results show that limited success would have been achieved by the microseismic system as a roof fall alarm trigger. However, the trigger would have been successful at warning of the onset of elevated activity, allowing mine employees to respond appropriately. The study highlighted some issues with implementing such a system in an operating mine, including the need for real time identification of fracture related microseismic signals among mining induced signals, and accurate location and identification of fracture clustering.

8053. Andreev, B. A. Zakashanakii, M. S., Samsonov, N. N., and Fotiadi, E. E. A Textbook of Gravitational -Surveying, (in Russian). Gosgeolizdat, Moscow-Leningrad, 1941, 432 pp. This textbook was written at the suggestion of-the faculty of geophysical exploration of the Leningrad Mining Institute. It contains two parts: (1) Theory and technique, and (2) Applications to geology and exploration. The features bringing; the text up-to-date include: (a) Description of the principal modern gravimeters; particular attention to the method of simultaneous oscillation of 4 pendulums; (b) discussion of the aperiodic oscillation of torsion balances; outline of the construction of variometers Z -20 and Z-40; (c) material for aid in interpretation, such as reference-charts, formulas with their derivation, atlas of theoretical curves, and examples of interpretative calculations; (d) considerations in the planning of surveys and the densities of various rocks; and (e) detailed analysis of significant examples. The text is provided with a bibliography, V. S.

Jan 1, 1946

By G. F. Skala

Additional testing of two prototype instruments for the discrete detec­tion of submicrometer particles in metal and nonmetal underground mines is described. The detectors are designed to utilize properties of submicrometer particles to distinguish between those produced by fires from mine ambient particles primarily resulting from diesel engine exhaust. One instrument is based on the ability to pyrolyze fire produced parti­cles, but not diesel exhaust particles. An alarm is produced when the ratio of pyrolyzed to unpyrolyzed particles exceeds a preset value. The other detector utilizes a continuous flow ion chamber preceded by a denuder to remove charged particles. Discrimination against diesel produced submicrometer particles results because the diesel particles are naturally more highly charged than fire produced particles. In-mine testing was conducted over a period of several months. Both in­struments exhibited an ability to discriminate against diesel exhaust. However, problems with the recording equipment, and with the instruments themselves, due to large ambient dust particles, prevented enough data from being obtained to choose between the two methods. Recommendations to correct the problems are made.

Jan 1, 1982

By Harry W. Campbell

A Bureau of Mines investigation identified no mineral deposits in the Lost Creek RARE II area. Sand and gravel has been mined from alluvial flood plain deposits just outside the RARE II boundary. An oil and gas lease application which includes the eastern portion of the RARE II area is pending. Abundant basalt in the area can be crushed and used as aggregate; but it could not compete with similar deposits in more favorable locations, or with cheaper substitutes such as volcanic cinders or sand and gravel which are available outside the study area closer to major markets. No indication of coal or geothermal energy resources was found. INTRODUCTION Location and Access The Lost Creek RARE II area encompasses 8,300 acres (3,400 ha) of Lassen National Forest in north-central California, about 20 mi (30 km) north of Lassen Peak. The closest city is Redding, California, 50 air mi (80 km) southwest. Peripheral access is provided by State Highway 89 passing near the western RARE II boundary (fig. 1). The Pacific Crest Trail traverses the western margin of Hat Creek Rim adjacent to the eastern boundary of the area.

Jan 1, 1983