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By A. L. Foote

This is the final report of work accomplished during 1973-75 under U. S. Bureau of Mines Contract No. H0242015, "System for Handling Underground Mine Supplies and Materials." The purpose of the contract was to develop a mechanical device which could safely perform handling tasks that are normally done manually in underground bituminous coal mines. The report discusses studies leading to construct-ion of a battery-operated, three-wheel vehicle with a six-degree-of-freedom manipulator. Supportive design studies included collection and analysis of production, manual functions, and injury data on the underground bituminous coal mining industry. Transfer tasks in section storage and working places were the prime candidates for mechanical handling. Functional specifications were developed for two handling devices (one to handle existing unit loads and one to handle repackaged unit loads) and for a vehicle to mount the handling device. Design concepts for nine different handling devices were developed and a cost/benefit evaluation made for each. Detail design, capital and operating costs, and method improvement savings data were developed for two battery-operated vehicles and for two different manipulators. The three-wheel vehicle with anthropomorphic manipulator was chosen for development.

Jan 1, 1978

By John E. Rourke, O&apos

This report documents the process of site selection, instrument installation, data acquisition, and preliminary data analysis followed to characterize the physical response of overlying strata to longwall mining. A system of surface, subsurface and mine level instrumentation was installed at the Allen Mine in Weston, Colorado where the overburden varied in thickness from 600 to 900 feet. Survey monuments, automatic-recording strain-meters, multi-point rod extensometers, inclinometer-extensometers, stressmeters and tape extensometer convergence stations were installed to monitor displacements and stress changes. A preliminary analysis of the data acquired up until project termination has shown the system to be operative and strata response to be similar to that reported for other subsidence monitoring case histories. Recommendations for continued monitoring of the instrumentation systems are presented.

Jan 1, 1982

By Andrew B. Cecala

The Bureau of Mines conducted a brief laboratory study on the 10-mm diam Dorr-Oliver nylon cyclone to investigate (1) whether high wind speed (>300 ft/min), or sampler inlet orientation with respect to wind direction, can introduce errors when sampling respirable dust, and (2) whether any such errors can be reduced by using an inlet shield. Being preliminary in nature, the study was not structured to produce definitive results, but rather to discern likely trends and to indicate whether or not a more in-depth study of the problem is warranted. Photometric mass sensing measurements suggested that as the wind velocity increased, the cyclone sampling directly into the high-velocity airstream tended to oversample, relative to the cyclone sampling in a low-velocity airstream. Orientation of the sampler introduced measurable differences in sampling efficiency at higher wind velocities. A shield placed around the cyclone diminished the effects of wind velocity and sampler orientation on sampler performance. Results of this work offer sufficient evidence to substantiate the need for a more in-depth study.

Jan 1, 1983

By R. A. Cummings

Certain roof shales in coal mines deteriorate upon exposure to the atmosphere, causing difficulties in the mining operations and adding to the cost. This report presents the results of both field investigations, in a West Virginia mine, and laboratory studies on the effects of atmospheric moisture on roof shales. Based on these observations, a conceptual procedure is presented on how shale deterioration might be predicted during exploration, and guidelines are given as to how air tempering or conditioning chambers may be designed to reduce moisture effects. Recommendations for further studies are included. An annotated bibliography of the literature constitutes the second volume.

Jan 1, 1981

By Paul H. Lu

This Bureau of Mines report summarizes the analysis and eveluation of the field measurement results of a comprehensive ground control study conducted in a mechanized longwall coal mine in West Virginia. Emphasis is placed on the three basic ground control parameters: ground pressure, ground movement, and geomechanical properties. Specific topics include premining ground pressures, front-abutment pressure in the longwall panel, histories of pillar loading, differential roof-strata movement and bed separation, differential floor strata movement, entry roof-to-floor convergence, in situ moduli of rigidity of coal seam and roof and floor strata, and mechanical properties of coal and coal measures rocks.

Jan 1, 1985

By J. McCoy

Charged sprays and fog have been evaluated for reducing respirable dust concen¬trations. Charged spray technology was reviewed for effectiveness, equipment and theoretical considerations. A mathematical model was developed for predicting dust reduction effects. Laboratory tests were made showing charged spray is considerably more effective at reducing dust on a unit water basis than hydraulic spray. Positive and negative sprays are equally effective. Combined polarity sprays are considerably less effective than either polarity alone. Little difference in effectiveness by dust type was observed. The charged cloud can present a spark hazard in explosive atmospheres. Due to this spark hazard from the charged droplet cloud this technique must not be used in gassy mines. Predictions were made for field test conditions but confirmation was impossible due to particles resulting from dissolved solides in the spray water. Dissolved or suspended solids in atomizing sprays can result in an increase of the respirable dust burden. Charged sprays are an available dust control technique best suited to applications where water usage must be limited and long contact time between spray and dust is possible.

Jan 1, 1983

By John W. Mentz

Phase I study efforts addressed: 1) acid mine drainage formation theory; 2) effects of inundation in reducing acid mine drainage formation; 3) summary information on the types of acid abatement technology currently available and the problems inherent in each; 4) analysis of two potential means of partially inundating abandoned segments of active underground mines to reduce acid formation. This subsequent Phase II Draft Final Report addresses all of the above, but concentrates on and defines Item 4. Seal construction techniques were taken through five logical steps as follows: A) Location Analysis; B) Coal Barrier Pillar Analysis: C) Ground Water Analysis; D) Design Considerations: E) Economic Analysis. The design details of both low wall dams and section seals were discussed in a series of segments: a) Case Histories; b) Feasibility Analysis; and c) Design (including representative calculations). Study efforts showed that both concepts are feasible only in certain mines where the geologic-hydrologic physical makeup is suitable to contain a mine pool. Low wall dams in particular were found to have extremely limited applicability as a means of pollution reduction. Section seals, while clearly dependent upon site specific conditions, have a some what broader range of utility and are more effective in pollution reduction. The proven dramatic reduction in acid mine drainage attributable to inundation makes this a concept that must be considered.

Jan 1, 1981

By Edwin M. Thomasson

HELIUM SHIPMENTS in 1964 exceeded the volume shipped during the previous year for the 15th successive time. Shipments from Bureau of Mines helium plants were 667.4 million cubic feet,2 about 6 percent more than in 1963. Production at Bureau of Mines plants totaled 784.5 million cubic feet. An additional 3,193.1 million cubic feet, which was produced by private companies participating in the helium conservation program, was purchased by the Bureau and stored underground for future use. The Bureau of Mines continued to sell helium at $35 a thousand cubic feet, the price established in 1961. Substantial railway freight rate reductions for tank car shipments of helium went into effect during the year, resulting in a lower delivered price for helium. As the Nation moved ahead in the space age, it became increasingly apparent that helium would continue to play an essential role in research, in technology, in defense, and in industry.

Jan 1, 1965

By Frank G. Horino

This report presents a method of utilizing the Coulomb strength criteria for estimating the strength and stability of pillars and pit slopes containing planes of weakness. It is assumed that the Coulomb theory, as a special case of the Mohr envelope, is a satisfactory first approximation of failure in uniaxial compression or triaxial loading with low lateral loads. Accepting this assumption for brittle materials, an expression for the strength decrease of rock pillars containing a plane of weakness or fracture at any angle of orientation is derived. As few as six samples (three solid cores and three fractured cores at a failure-oriented angle) are required for testing uniaxially and triaxially to statistically determine the coefficients of friction and the shear strengths of both the solid rock and the fracture plane and the range of failure angles of the fracture plane. Interpretation of the data shows that the mean normal stress and maximum shear stress technique of analyzing the data is superior for solid core and that shear and normal stress values using angles of failure should be used for fractured specimens with failure-oriented angles. Plots of either the strength or strength ratios against fracture angles obtained from oriented drill core samples give a useful first approximation of strength decrease due to fracture. Using the same test conditions for both fractured and unfractured material increases the validity of the tests.

Jan 1, 1970

By Jesse J. Brown

Over 60 simple; were prepared and forwarded to Dr, S. Z. Toma, TPO, PMSRC as a result of this project. Included among these samples were various low temperature forms of silica. Samples of quartz, cristobalite, and tridymite with iron, manganese, and titanium impurities present were prepared. In addition, a long series of samples both wet ground and dry ground for times from 1/2 to 8 hours were prepared. Numerous miscellaneous samples were submitted which included kaolinite, calcite, muscovite, illite, montmorillonite, Ba3(P04)2, and YPO4 among others, in response to special requests from the TPO. The silica rich portion of selected binary (CA 203-Si02, In 203-Si02, Li20-Si02) Na20-Si02, PbO-Si02, SnO2-Si02, Sn02-Si02 BaGa204-SiO2 and SrGa204-Si02) and ternary systems (Na20-Ga203-Si02 and Li20-Ga203-Si02) was investigated to determine the effects of solid solubility on the stabilization of the high temperature forms of tridymite. In addition to the determination of the extent of these crystalline solubilities, observations were made. on the mechanism of the transformation of silicic acid to tridymite and the rate of the reaction in the presence of foreign ions,

Jan 1, 1973

By S. M. Shelton

Ferrograde manganese ore or its equivalent is essential to the manufacture of every ton of steel produced; although it is well-known that there are largo deposits of low-grade ore in the United States, production of substantial amounts of ferrograde material from domestic sources presents a problem that becomes more and more critical as the stock piled ore is depleted through inability to obtain adequate supplies from foreign sources. Consequently, a program of laboratory and pilot-plant investigations designed to solve the problem of obtaining a domestic supply of manganese has been undertaken by the Metallurgical Division, Bureau of Mines. This paper is one of a new series that will include reports of results obtained in the various investigations conducted under the manganese program. The scope of the program and the organization that was set up to direct and supervise the work were discussed in the foreword of the first paper of this series, Report of Investigations 3506, Manganese Investigations 1. Concentration of Manganese Ores from the Drum Mountain District, Utah, by S. R. Zimmerley, J. D. Vincent, and C. H. Schack. Other reports will be published as the work progresses.

Jan 1, 1942

By J. M. Pugliese

The Bureau of Mines, in support of its overall goal of helping to meet future U.S. demand for minerals, undertook this study to aid the quarry entrepreneur and/or operator in developing quarries near urban areas. In response to increased environmental concerns, the quarry operator often must take steps beyond those required in the last decade toward gaining permits for quarrying near metropolitan areas. Following the steps suggested in this report should increase the chances to obtain the permits to open and develop a quarry. Each task and question in the general plan flow diagrams are described in detail, with the flow diagrams aimed at the goal of acquiring the necessary permits. The appendixes include (1) types of projects for which Environmental Impact Statements (EIS's) may be prepared and Federal agencies responsible for preparing them, (2) State contacts for information regarding environmental impact assessment requirements and mining and mineral land reclamation laws, (3) a checklist of environmental inventory factors, (4) a tabulation of different regulations that affect mining in Michigan and the number of townships and counties that have each of the listed regulations, and (5) environmental logic associated with site selection. A central recommendation is that the quarry entrepreneur and/or operator coordinate plans at the beginning with local government officials (such as township supervisors and/or city and county planning board members), State and Federal officials, and public groups that will be affected.

Jan 1, 1979

By G. E. Geiger

The purpose of this research was to develop a computer simulator fur predicting the air quality in existing coal mines as well as a design aid for developing new mines. In addition to the air quantity flow, the other variables of tempera Lure, moisture, methane and respirable dust are necessary to determine the air quality. An additional feature of this simulator is that it allows parametric studies of these variables to explore the effect that these variables have on the air quality of an operating mine system. The research has also pointed out arias where more research is needed, and promote better and more systematic data taking techniques. Wang and Hartman (see Reference 9, on page 1-98 of Section 1) had already published a computer program to determine the ventilation of large mines, and Wang and Saperstein (see Reference 10 on page 1-98 of Section 1) later published a refinement of the work in the previous reference. These references were the starting point of the simulator developed by this present research effort, and Section 1 of this report is a slightly modified version of the original vent elation program. The modifications were necessary to permit the additional programs of temperature-moisture, methane and dust to be

Jan 1, 1972

By Donald E. Redmon

This Bureau of Mines report examines the injury experience in the quarrying industry For the years 1966-67. Twenty-eight tables for each year are presented in which disabling work injuries are summarized by department, source of injury, extent or disability, part of body injured, and nature of injury. Correlative information on employment, worktime, and operating activity is also presented.

Jan 1, 1973

By Adrian Brown

Pilot Hole ?X? was drilled to test the formations through which the ventilation shaft for the proposed U.S.B.M. demonstration oil shale mine will be drilled. Five permeability tests were performed at various stratigraphic levels within this hole. The test method used was that of pumping fluids out of the hole for three hours, using the air lift method, followed by a three-hour period where the recharge was observed. Transmissivity and permeability results were determined from these test data. The test procedure used is described and supporting data for the hydrologic tests are provided.

Jan 1, 1977

By Jr. Frank Parrish

This report describes the performance of 17 selected water-injection projects producing from Pennsylvanian-and Permian-age reservoirs. Illustrations depict reservoir structure and thickness, and production and injection history. A selected bibliography of publications pertaining to area oil recovery and geology is included. Tabulations of field and reservoir data reveal marked differences in the projects. Increased oil recovery resulted from injecting water in most cases; however, seven projects recovered less oil than the operators anticipated. Oil recovery by water injection ranged from 0.2 to 262 bbl per acre ft, or 0.1 to 22.5 pct of the initial stock-tank oil in place. Major reasons suggested for poor performance include: (1) Adverse directional horizontal permeability, (2) channeling of injected water through fractures or zones of high permeability, and (3) lack of containment of injected water. One 330-foot-deep project is among the first successful shallow water-floods in north Texas. Another project is the first successful Canyon sand-stone waterflood reported in the area. Previous gas injection in two Cisco sandstone projects did not prevent the reservoirs from responding favorably to waterflooding.

Jan 1, 1965

By P. B. Grote

The report provides a general description of DOM technology, sources for DOM technology, and identifies approaches and requirements for acquisition by the Enterprise of DOM technology by conventional means. The approaches identified assume the Enterprise enters into a contractual/ joint venture arrangement with an uncommitted and competent systems management firm at various stages of the DOM system acquisition process. The approaches provide for training through work/study as well as through direct participation in acquisition programs. The potential success of the alternatives are evaluated in terms of the likelihood of the acquisition of an ongoing Enterprise economic DOM operational capability. The study concludes that sources exist and that the Enterprise should under-take the development of its own technical capability through conceptual design prior to selecting its source for systems management expertise.

Jan 1, 1980

By J. Mitchell Linne

In 1986 at the request of Bureau of Land Management, the U.S. Bureau of Mines studied 23,225 acres of the 27,980-acre Jordan Craters Wilderness Study Area (OR-003-128) in order to evaluate its identified mineral resources. The study area is located in Malheur County, OR, about 20 miles northwest from Jordan Valley. No mining activity has been recorded within the study area, and no metallic or industrial mineral resources were identified. Small isolated occurrences of decorative quality stone were identified. However, none of these occurrences constitute a resource. Although the study area is underlain by relatively young volcanic rocks, the area has no known geothermal energy resource.

Jan 1, 1987

By S. M. Shelton

Tests employing various ore-dressing methods were made on a manganese wad ore from the W. A. Chinn property in the Batesville-Cushman district of Arkansas in an effort to develop a practicable procedure for the production of ferromanganese-grade concentrates. The ore body occurs as a bed approximately 7 feet thick in the residual clay of the Ferndale limestone formation5/. The crude wad ores are soft aggregates of various oxides of manganese, which are loosely bonded together. Hard lumps of high-grade ore are disseminated throughout the wad. Hausmannite, pyrolusite, and psilomelane are the principal minerals. Some clay is present, but most of the gangue consists of leached fragments of the original siliceous and calcareous rocks in which the manganese occurred. In addition, hydrated oxides of iron, which axe present, also must be considered as gangue. Definite phosphate minerals have not been identified.

Jan 1, 1942

By Robert L. Lagace

A whole-mine experiment to assess the practical feasibility and utility of the dedicated-wire technique for overcoming poor trolley carrier phone system performance at a large underground coal mine was designed, performed, and evaluated. The technique involves the use of a single, low-loss, properly terminated and branched auxiliary wire placed in the rail haulageway. This auxiliary dedicated wire allows signals to electromagnetically couple to the trolley wire/rail transmission line, and thereby significantly decrease the overall signal attenuation rate on the trolley wire/rail line. The in-mine dedicated-wire demonstration program and its results, conclusions, and recommendations are described. The dedicated-wire technique is shown to be a valid and practical one for significantly improving carrier phone system performance in coal mines.

Jan 1, 1981