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This Volume documents the Phase 111 effort on the Seismic Detection and Location of Isolated Miners on Contract H0122026 undertaken during the fall of 1972 by a task team composed of ADL staff and several seismic consultants. The team was assembled specifically to work together on complementary tasks, at an accelerated level of effort for four months, to meet the Bureau of Mines' time schedule for obtaining independent, objective, technical judgments regarding seismic methods and systems for detecting and locating isolated miners. The impetus for this work resulted from a compilation and analysis, during the first half of 1972, of new experimental data obtained from a series of in-mine field tests conducted by Westinghouse Corp .+ using the CMRSS* interim seismic location system. The Bureau of Mines took advantage of the availability of these new data to reassess the potential and limitations of various seismic methods and systems, and to direct its seismic system improvement program accordingly. ADL assisted the Bureau in this reassessment by drawing on the skills of seismic consultants from industry, universities and government, to supplement the skills of the ADL project team. The consultants were principal resources of broadly-based and detailed technical expertise in the areas of seismic signal-source and signal-propagation characteristics, natural and cultural seismic noise, seismic sensors and field instrumentation, seismic signal and data processing for detection and location, and overall seismic system utilization in the field under operational emergency conditions. Specifically, the participating consultants were: F. Crowley, Air Force Cambridge Research Laboratories ; W. Dean, Teledyne Geotech, Alexandria Laboratories; R. Greenfield, Pennsylvania State University; J. Kuo, Columbia University; D. Peters and R. Crosson, University of Washington; and F. Pilotte, U.S. VELA Seismological Center. The principal ADL participants were J. Ginty, R. Lagace, M. Roetter, and R. Spencer.

Jan 1, 1974

By Harry Teicher

The subject of Specialty Silica Products could encompass a broad range of materials, some of which would be familiar to members of the Society of Mining Engineers. With the concurrence of your chairman, I have chosen to limit my remarks to synthetic materials, not including such siliceous materials as diatomaceous earth, asbestos, quartz and clays. For purposes of discussion, I have classified Specialty Silica Products into two groups -- powders and liquids -- which I will discuss in that order and which are categorized in Figure 1. The synthetic silica powders are amorphous to x-rays and are manufactured by various processes resulting in products of a wide range of physical and chemical properties, as well as functional performance and applications. Applications or functional properties are generally dependent upon such physical properties as micron-sized particles exhibiting large surface areas per unit weight and low apparent bulk density. Their presence in various systems modify surface properties. As summarized in Figure 2, they act as viscosity modifiers, flow conditioning agents, anti-slip agents, anti-blocking agents, flatting agents in surface coatings, reinforcing agents in polymers such as silicone rubber and numerous other applications. Although the various types of silicas exhibit various levels of functional performance in these end uses, they are not usually equally effective as direct replacements and I will briefly discuss the various types of materials.

Jan 1, 1974

By Charles T. Ford

Limestone neutralization of acid mine drainage has been proposed and examined as a method of treatment. However, limestones differ greatly in composition and structure. The reactivity of 14 selected limestones was studied, both by chemical and physical properties and by relative effectiveness in neutralizing synthetic and actual mine waters, and several guidelines for the choice of limestones are given. The particle size should be at least as small as 74 microns and preferably smaller. The most effective limestones are most nearly pure calcium carbonate. Stones which have a relatively low calcium con- tent but which contain calcite and have a large surface area are also effective neutralizers. Magnesite and dolomitic limestones are much less reactive. Disadvantages in using even the most reactive lime- stones for neutralization are indicated.

Jan 1, 1974

In this paper, a subtle, but important, difference has been drawn between responsibility and mandate. Responsibility has a connotation of financial involvement assigned to an organ- isation as a result of some action it takes, the ramifications of which can be ascribed directly to the organisation. In contrast mandate relates to the power and authority to act. The paper outlines the role of poli- ticians as community decision-makers and the need for Government policy to be flexible in an advanced industrial society so that decision- making options are kept open for as long as necessary. Further, broad community objectives need to be understood and defined so that plans and policies can be consistent. Co-ordination through communication at all levels, especially at the public administration interfaces and with the private sector,is essential for effective resource allocation and efficient implementation. The paper discusses several aspects of the infrastructure responsibility question and some considerations which might be viewed as important by the community decision-makers in considering what responsibility the "community" should accept in providing infrastructure.

Jan 1, 1974

By Fred N. Kissell

Methane concentration peaks were measured by the Bureau of Mines at coal mine working faces during entry development. The statistical distribution of peaks was found to be normal or log normal depending on how well the methane was being mixed into the ventilation airstream. A normal distribution indicated good mixing, whereas a log-normal distribution indicated that mixing was poor. In addition, the "highest" peaks over selected intervals were found to fit a type I extreme-value distribution, a result similar to that obtained while mining longwall faces.

Jan 1, 1974

By R. L. Braun

In situ chemical mining of primary sulfide ore requires distribution of injected oxygen in a large underground flooded region of broken ore. Although the maximum oxygen content of the leach solution will be dictated by the operating temperature and hydrostatic pressure, the actual oxygen content will be limited by the geometric dispersion of the injected oxygen, the rate of dissolution of oxygen, and the rate of convective circulation of oxygenated solution within the flooded bed of ore fragments. These factors are examined by a detailed theoretical analysis supported by laboratory experimental data. Typical results of the study illustrate that adequate dissolution of oxygen and circulation of oxygenated solution can be obtained in a column of 4 million metric tons of broken ore by using three gas injection lines and an oxygen injection to consumption ratio of 1.84.

Jan 1, 1974

By John D. Morgan

The United States is the world's most productive nation and its citizens enjoy one of the highest material standards of living of any people in the world. Materials and energy are the lifeblood of any industrialized economy. Annually the United States uses over 4 billion tons of mineral materials and fuels, or 40,000 pounds per person as detailed in Figure 1. Domestic processed materials of mineral origin and energy are valued at more than $150 billion annually, and they are derived largely from domestic sources, supplemented by imports, as detailed in Figure 2. In recent years the superior productivity of the United States has also enabled it to give food and manufactured articles to many other less fortunate nations and peoples of the earth. What then is our concern with materials at this time? Seeing the burgeoning increases in our mineral demand: from 2 billion tons in 1950, to over 4 billion tons today, and projected to 11 billion tons by 2000 - we are getting questions concerning our ability to continue to increase production sufficiently for the future.

Jan 1, 1974

By David E. Kaslow

In sampling dust laden air by drawing the medium into an inlet, some larger particles fail to follow the air and a true sample is not obtained. Inertia prevents particles from accelerating with the air as well as from turning sharp bends; also the particles' weight causes them to fall relative to the air. An analytic solution to the sampling efficiency calculation by Levin gives particle paths and sampling efficiencies for various particle sizes when the inlet can be treated as a point sink. However, the flow field in the neighborhood of an aspirating tube is quite different from a point sink flow. Employing Levin's solution in the outer field, trajectories in actual flow fields have been calculated by computer to locate the critical trajectories separating the entering particles I paths from those paths where the particles hit the tube wall or escape. Sampling efficiencies are presented in terms of 3 variables--a dimensionless particle size coefficient, a dimensionless orifice size coefficient and the tube orientation--for the no-wind case. Over most of the range of sampling conditions, the Stokes drag law can be used and dependence on the variable--particle Reynolds number--can be ignored. A procedure for achieving maximum efficiency in design of a sampler is proposed. Whether these results apply when typical room-sized eddies constitute the ?calm air? environment is not known.

Jan 1, 1974

By Warren E. Fife

This paper will discuss the application of a continuous miner using a fixed drum milling type cutting head for the underground mining of hard rock and salt ores. Continuous mining machines of the ripper chain cutting head, oscillating milling cutting head and boring arm designs have been used in rock and salt applications with various degrees of success. The large boring arm miners have been successful in potash, trona and salt, but they have not been successful in mining rock materials like iron ore. The main method used in underground mining rock materials is the conventional drilling and blasting the ore from the solid. This is particularly true for the harder, more abrasive copper and iron bearing ores. The softer salt based ores of potash, trona and rock salt can use several underground mining methods depending on seam conditions. Several of these methods use underground coal mining equipment that has been extensively redesigned to adapt it for use in mining noncoal materials. Conventional mining methods employ the use of a universal cutting machine to undercut or topcut the ore body before face drilling and blasting takes place to produce a smooth parting of the ore. The boring arm continuous miner is widely used in underground mining of potash and trona ores. It produces a tunnel with a smooth semicircular contour which results in good rib and roof stability. The ripper chain continuous miner is also widely used in mining the salt based ores of potash, trona and rock salt. They are used more frequently in Europe than in the United States and Canada. Some reasons for using the mechanical mining machines as opposed to the conventional drilling and blasting techniques for mining hard rock ore bodies are the resulting improved rib and roof control, facilitates selective mining of the ore body, and requires less man-

Jan 1, 1974

By G. R. Goldak

All of Canada's older uranium mining areas have been intensively prospected and known outcrops have been repeatedly examined. The only ground in these areas which has not been explored is that which is covered by water or other overburden. The discovery of new mines in these areas will, in the author's opinion, depend on the development of new geophysical or geochemical tools capable of locating uranium deposits which are-buried beneath tens to hundred of feet of overburden. Such tools would be extremely useful in Saskatchewan's Cluff Lake and Wollaston Lake areas. Uranium has recently been discovered in significant quantities in these regions but exploration is made extremely difficult and expensive by an almost uniform overburden cover. The author's experience has been confined to Canada but apparently a subsurface uranium prospecting method could be widely exployed in the western United States and Australia as well. Radon-222 measurements have been used for more than a decade on practically a worldwide basis in an attempt to obtain a useful method for subsurface uranium prospecting. It is well known that ha-222 produced by buried uranium deposits can diffuse through an overburden cover so that it can sometimes be detected at surface. An advantage of this method of prospecting is that Rn-222 can be detected with a simple scintillation, ionization or semiconductor detector. One of the essential weaknesses of the method is that the mean diffusion path length of Rn-222 is limited by its very short (3.8 days) half life. For a deeply buried deposit, vitually all of the Rn-222 atoms will decay before reaching surface and, therefore, such deposits cannot be expected to produce a detectable radon anomaly. Thus, except in unusual cases where groundwater or ground air flow assists the movement of radon towards surface, the depth of exploration is probably limited to ten or twenty feet of overburden cover. The high solubility of Rn-222 in water is also a source of difficulty. In an area where overburden covers bedrock with water saturation of the lower overburden levels, the radon will simply dissolve in the groundwater, and soil gas readings at surface will indicate falsely low

Jan 1, 1974

By Raymond T. Moore

The Federal Coal Mine Health and Safety Act of 1969 (FCMHSA) begins with this statement: "Congress declares that the first priority and concern of all in the coal mining industry must be the health and safety of its most precious resource -- the miner; . . ." At the Federal level this responsibility is shared by the Department of the Interior and the Department of HEW. The health research and standard setting activities under the Act are largely the responsibility of the Department of HEW, and with the exception of Title 4, Black Lung Benefits, have been delegated to our Institute, which I will refer to henceforth as NIOSH. In addition, we bear certain joint responsibilities with the Department of the Interior. These include dust sampling and respirator approval. To complete the picture, the Department of Labor has recently assumed Black Lung Benefit respon¬sibilities from the Social Security Administration under Title 4 of the Act.

Jan 1, 1974

By R. A. Paul

The requirements for water inflow control for the Chicago Intercepting Sewer System are stringent. This posed special problems in grouting the bored and conventionally mined tunnels, shafts and chambers of the system. In adapting conventional grouting techniques to the specific problems encountered in the system's pilot project, numerous field procedures were developed. Careful preand post-grout testing and evaluation identified the most efficient and economical of these procedures. As an example of some of the conclusions reached during the project it was found that the mineralized groundwater in the Chicago area tended to reduce the efficiency of the grout holes, thus limiting their useful life. Pressure washing to remove natural fillings was a critical factor in achieving a permanent grout seal. The value of relatively thin lubricating grout mixes was definitely established. Although not an ideal situation, satisfactory results could be obtained by manifold grouting several grout holes simultaneously if done within specific limits of hole groutability, location and numbers. Caulking proved to be a primary controlling factor in achieving acceptable results. To achieve such a high degree of water inflow control requires close supervision by experienced personnel. "Temporary grouting as a construction expedient" produces seepage conditions which are extremely difficult to treat.

Jan 1, 1974

By E. D. Calvert

The room temperature tensile properties of commercially pure titanium and seven titanium alloys prepared by skull casting were determined in the as-cast and heat-treated conditions. Data were compared with property data from tensile tests on wrought alloys of the same compositions in the as-worked and heat-treated conditions. The alloys evaluated were Ti-5Al-2.5Sn, Ti-6Al-4V, Ti-6Al-4V-lSi, Ti-6A1-2Sn-4Zr-2Mo, Ti-6A1-6V-4Zr-4Mo, Ti-6A1-6V-2Sn, and Ti-11.5Mo-6Zr-4.5Sn. Test specimens were prepared from both static and centrifugal castings and from plate fabricated by forging and rolling vacuum-melted ingots. The data indicate that the alpha and alpha-beta alloys have strength properties in the as-cast condition that are reasonably close to the strength properties of their wrought counterparts in the as-worked condition. An exception to this was the Ti-6A1-6V-4Zr-4Mo alloy for which insufficient data were available to form any firm conclusions. Fine-grained cast structures of Beta III (Ti-11.5Mo-6Zr-4.5Sn) were shown to be generally stronger in the as-cast condition than the wrought alloy in the as-worked condition except for the yield strength of one structure that was unusually low. Heat treatment of this alloy produced properties that were unpredictable. Indications are, however, that optimization of heat treatment parameters for each cast structure could produce strength properties equal to that of wrought materials.

Jan 1, 1974

The safety in pillar extraction is closely allied to the design features of the pillar extraction system. Considering the conventional supported systems of pillar extraction there are problems associated with complying with the design system outlined. The accident causing agencies and the legislative action to overcome them are im- portant aspects. There is merit in the regularity of support and the limiting of the effects that human error can cause. But new problems and hazards are introduced by this powered support equipment. The comparison of accident experience is difficult due to lack of records and lack of uniformity of approach, but it is clear that powered supports provide a safer system. Every progress in research and practice provides further data to employ in accident prevention.

Jan 1, 1974

By F. X. Meagher

Vertical slot raise driving from bottom up has always been a hazardous, inefficient, high cost operation. The introduction of the Simba 5 drill rig has enabled this type of raise to be drilled accurately from the top down and to be blasted in stages from the bottom up. Safety, high efficiency and low cost were the main criteria in opting for this method. Drop raises with the Simba 5 at Geco have been successfully drilled and blasted up to 115 feet, and this is close to the maximum length of raise that can be drilled and blasted efficiently with Simba 5. A look into the future would indicate a rig capable of drilling up to 200 foot raises with the same accuracy of Simba 5 to 115 feet.

Jan 1, 1974

By Birger Schmidt

INTRODUCTION Urban tunneling in soil poses a unique set of problems to planners, designers and contractors. One of the important concerns is the impact of tunneling on the environment: not only the effects of noise, vibrations, construction traffic and surface traffic diversions, but also the effects of ground movements and dewatering on existing structures and facilities. Underpinning or other protection of structures often consume more than 10% of the total construction cost of an urban rapid transit tunnel, and another unknown percentage is expended on construction procedures designed to minimize these environmental effects. Ideally, many basic planning and design decisions should be based on reliable predictions of ground movements due to tunneling. Some of these decisions are: the choice of tunnel alignment and depth to minimize risks and effects of ground movements; selection of schemes to protect existing structures through soil improvement or underpinning, or outright acquisition and possible' demolition; relocation of utilities; selection of procedures for construction monitoring and project control; and the choice of construction and lining methods. To make rational decisions of this nature, the owner and his designers must perform analyses that will balance risks and costs of a variety of alternatives; but to make meaningful risk analyses, they must employ rational methods of predicting ground movements and their effects and must know the reliability of these predictions. Of course, the risk analyses also must consider politics, public relations, insurance and liabilities.

Jan 1, 1974

By Bert Woodhouse

The excursions - Symposium on Ancient Mining and Metallurgy in Southern Africa by BERT WOODHOUSE Excursions add much to any symposium. They enable the participants to see something of the subject matter, and provide an opportunity for informal discussion and for the creation or renewal of friendships. In this respect the Ancient Mining Symposium was well provided for. There were two excursions and both were repeated to cope with the large number of participants.

Jan 1, 1974

By P. G. Pigott

This investigation by the Bureau of Mines demonstrated that building bricks can be produced by the steam-curing process from various types of industrial mineral wastes. Wastes, utilized to produce bricks, consisted of copper mill tailings, roofing granule fines, asbestos fines, and zinc mill tailings. Bonding of the wastes with either Ca(OH)2 or portland cement resulted in building bricks that met ASTM specification C73-67 for grade SW and MW bricks when evaluated in accordance with ASTM designation C67-66 on sampling and testing of brick. An economic evaluation of the process indicates the total operating cost per 1,000 bricks is about $36.

Jan 1, 1974

By F. N. Kissell

The Bureau of Mines has successfully used sulfur hexafluoride (SF6) as a tracer gas to measure mine air flows under conditions where conventional methods have failed. SF6 was employed experimentally to measure accurately recirculation of return into intake air caused by leakage through an old stoped area, to check for potential leakage from an adjacent mine, to trace 10,000 cfm of “lost” air from an intake airway, and to measure transit air time through uranium mines. It proved useful as a means of accurately measuring airflow volumes in airways of large cross section and very low flow velocity, and in determining the recirculation resulting from underground cooling plants.

Jan 1, 1974

By Edward K. Davison

The so-called "construction aggregates," sand and gravel, crushed stone, and several kinds of metallurgical slags, are used principally in the construction and maintenance of all kinds of roads, engineering structures, buildings, homes, airports, etc. Production of these aggregates is approaching two billion tons annually. In terms of tonnage produced, sand and gravel has been the leading mineral since 1954, with crushed stone gradually approaching an equal tonnage. Sand and gravel is of widespread occurrence and of wide variation in suitable gradation and quality. It is a low-value, heavy-loading, short-haul commodity. These characteristics account for the historic concentration of production tonnage in and near urban areas where construction activities are concentrated. The combination of improved urban and near-urban highway systems and the steadily rising rail rates for short-haul traffic has fostered a consistent change since World War II from rail to truck transport, with trucks now accounting for more than 807 of the tonnage moving away from the production sites. While there are increasing numbers of exceptions, truck transport of sand and gravel is generally limited to about 30 miles. The expansion of the urban and near-urban areas of even moderate density, which became so pronounced after World War II, has been the source of most of the sand and gravel industry's environmental difficulties. Dust, noise and truck traffic associated with the operations -- particularly truck traffic -- have, of course, generated public complaint. This has been particularly true in those many cases where housing developments have approached and even surrounded sand and gravel operations which were in operation before the development started.

Jan 1, 1974