Search Documents

By F. A. Renninger

The terms environment and environmental control, when used in today's context, generally imply to the average individual, something to do with pollution and pollution control. These latter terms, likewise, impart visions of fouled air and dirty water attributable largely to the industrial segment of American society. We have been conditioned, by various means, over the past ten years to equate environ¬mental control with pollution control. We have been trained to think of industrial environmental control programs as efforts conceived only to comply with one or more of the recently imposed pollution control regulations. Almost automatically we; approach consideration of environmental control with a degree of pessimism that is we assume that pollution prompted the control program. It is the purpose of this discussion to demonstrate that environmental control. at least as it exists and has existed within the crushed stone industry, involves far more than simply control or reduction of air and water pollution. It involves a dedication to the enhancement of each of the several "mini-environments" which together comprise the total world surrounding any given crushed stone operation. Environmental control, exercised properly, is an optimistic, constructive, forward-looking, enhancing type of activity. It is a function which has been, and should continue to be, willingly and expectantly undertaken by informed management personnel. In short, environmental control. is an activity from which both industry and society can and should benefit.

Jan 1, 1972

By Daniel B. Brimhall

The research presented here was initiated to investigate the role of atmospheric oxygen in the leaching of copper waste dumps. The problem of increasing the recovery rate of copper from these dumps is or great importance considering there are by conservative estimate in excess of fifteen billion pounds of copper located in dumps in the western United States. At this time, there is an increased interest in recovering copper from these dumps on a large scale. Large tonnages of low-grade material are being placed on the waste dumps of most copper mining operations in the western United States each day. The size of these dumps ranges from 5.5 million tons at Mineral Park, Arizona, to 4 billion tons at Kennecott's Utah operation (1). Leach solutions are recycled and contain ferrous and ferric sulfates. Large quantities of dissolved aluminum, magnesium and calcium salts may also be present. To this solution make up water is added to maintain the solution inventory and sulfuric acid is added for pH adjustment. Iron is introduced into the leach solution by the dissolution of the iron-containing sulfide and oxidized minerals present in the ore deposit. In addition to the iron from dump leaching, iron is also introduced during the precipitation process when the pregnant solution is passed over metallic scrap iron if cementation is used to reduce the copper in solution.

Jan 1, 1972

When the Middle Ages were drawing to an end and Rotterdam, then still a small fishing port, began to extend its trade relations to continental ports handling general cargo, a development was initiated which was to give Rotterdam a predominant position in maritime traffic in Europe 300 years later. Despite many setbacks and the silting up of the mouths of the Rhine and Meuse rivers, the port experienced a new rise towards the end of the previous century after the dunes at Hook of Holland had been cut through as planned by Dutch engineer Caland. With its favourable location in the mouth area of the Rhine and a hinterland opened up by waterways it was merely a matter of the city council pursuing a far-sighted policy to make the best of these natural advantages. Thus new port installations were erected on the southern bank of the Meuse in the first quarter of this century, which were expanded in the course of the subsequent decades. The New Waterway became the main artery for industrial enterprises, in particular oil industries, which sprang up along its banks (picture 1). Whereas 30 years ago Rotterdam's Waalhaven, with its new jettees for general cargo and mainly bulk goods, was still one of the most modern terminals, the growing size of ships, which increased by leaps and bounds for tankers, in particular towards the end of the 'fifties, necessitated much larger harbour facilities built further and further towards deep water.

Jan 1, 1972

This section contains a summary of our investigation of the soil conditions (type, porosity, moisture content, etc.) at the two sites (Lanse and Kato, Pennsylvania) selected for field testing of latex as a soil sealant. Other natural conditions such as rainfall, frostline, depth of the water table, etc., were also measured and recorded for possible later use in assessing the effect of the latex seal on the total environment. The numbered sites referred to throughout this report are shown on the maps of the Lanse and Kato sites (Figures 1 and 2). KA, RB and KC are positions at the Kato site - all other numbered positions refer to the Lanse site. Two other terms used throughout the report which should be explained are “horizon” and "profile". These are synonymous terms for soil layer, A horizon (or A profile) referring to topsoil and B horizon (or B profile) referring to subsoil. The properties that control the flow of water through the soil are of special interest because these will also govern the passage of a sealant into and through the soil. Normally the particle size distribution is a good measure of soil permeability, which is directly proportional to sand content and inversely proportional to silt and/or clay content. Tables I1 and I11 show the percentages of gravel or stones, sand, silt and clay of Lanse and Kato soil samples. According to the United States Department of Agriculture classification, the gravel is ,ignored and the residue separated into sand, silt, and clay fractions. Figures 4 and 5 indicate by means of the USDk soil texture triangle that the variability of composition of Lanse soil ranges from sandy loam in the creekbed to clay loam. The variation is even greater among soil samples from Kato. Porosity of soil, also known as percent voids, is another indication of how readily water will travel through soils. Soil density usually increases and porosity decreases with depth, and as expected, the porosity of the top soil at Kato, a forest, is exceptionally porous and open (see Table IV) The pore diameter and length of soil capillaries is extremely variable, and its distribution in the field is impossible to determine. In addition to the capillaries, soil also contains many macro cracks, crevices, and passages around stones and roots. All these affect the flow rate of water through soil. Poiseuille's law states that the rate of flow of a liquid through a narrow tube is proportional to the 4th power of the radius of the tube. Pore size normally decreases with depth and in soil containing appreciable amounts of silt and clay this is especially true. Thus, deeper soils should be less permeable and such was the case at Lanse and Kato.

Jan 1, 1972

By Michael R. Grubbs

The Bureau of Mines is currently developing methods for reclaiming the metal and mineral values contained in unburned urban refuse. One important phase of this research deals with recovering Mastic from shredded refuse using in electrodynamic separation process. The results of this study have indicated that mixed plastic concentrates analyzing 99.4 percent plastic can be consistently recovered from the light material fraction of shredded refuse, leaving a mixed paper traction analyzing 99.9 percent paper. Recovery of the plastic exceeds 99 percent.

Jan 1, 1972

By D. A. J. Swinkels

The problem of determining oxygen levels in liquid steel to aid in deoxidation control has received general attention for a number of years. Work in this direction started at the B.H.P. Central Research Laboratories early in 1967 with an evaluation of sampling techniques followed by vacuum fusion analysis to determine the oxygen content of the samples (1). It was found that these techniques had a number of drawbacks if they were to be used for deoxidation control. The method of analysis was rather too slow to allow effective control and measured total oxygen level rather than dissolved oxygen. Furthermore, the results were found to be very variable due to slag entrainment in the samples. Attention therefore turned to the galvanic cell method using a solid oxygen ion conductive electrolyte such as cubic stabilised zirconia. The ionic conductivity properties of electrolytes such as (ZrO2) 85 (CaO).15 had been studied by a number of investigators and had already been applied to the measurement of oxygen activity in gases, in lower melting metals such as copper, lead, tin, silver, alkali metals and indeed the first studies in steel had been made (2,3). Since then the results of a number of studies in the development of an expendable oxygen probe for steel have been reported (4-9).

Jan 1, 1972

Silica reacts with cryolite at 1010°C in two stages. The first stage is the formation of a sodium aluminosilicate of composition consistent with the mineral jadeite (Na20.AI20s.4Si02). The formation proceeds by atleast two different reactions. Formation of alumina or an aluminosilicate proceeds to its limiting value in the first 30 min while the formation of jadeite proceeds at a steady rate until quantitative conversion is achieved after 150 min. The net overall reaction can be expressed by the equation 6 Si02+2 Na3AlF6? (Na20.AI20s.4Si02) +2 SiF4 +4NaF.The second stage involves a slow reaction that proceeds with the evolution of a little SiF4, The net result is the formation of sodium aluminosilicates that are soluble in 30 per cent AlCIs-HCI solutions. While this could be explained by disproportionation of jadeite to form albite (Na20.Al203.6Si02) and nepheline (Na20. AI203.2Si02), it is more likely that it is due to further but limited reaction between the oxides and fiuoroaluminates.

Jan 1, 1972

By Robert E. Carver

Opaline clays from central and eastern Georgia are widely used as industrial and domestic absorbants, principally as insecticide carrier and animal litter. The clays are classified as fuller's earth, although they &e somewhat atypical of the group, since opal (cristobolite) is commonly the dominant clay-sized mineral. A preliminary investigation of absorption characteristics indicated that water vapor absorption (264 days) is' related to opal content as determined by x-ray diffraction peak height ratios. Ethylene glycol vapor absorption is related to montmorillonite content. Contact absorption of water is complexly related to surface absorption, porosity, opal content and montmorillonite content, and may be as great as 112% of the original sample weight. The most absorbent clays are highly porous (to 65%) and contain both montmorillonite and opal.

Jan 1, 1972

By J. W. Sweeney

The .Florida land-pebble mining industry of central Florida was examined to identify trends in land use; conflicts in land use; and the effect of the conflicts on mineral resources. Many conflicts exist in the study area, such as conflicts with other users of land resources and land surface; conflicts with high revenue land users; conflicts for land surface in urban and suburban areas; and conflicting restrictions concerning utilization. Projections are made showing that lands in phosphate company ownership are expected to be made available to help meet the need for future urban expansion in the study area. Some phosphate resources have been lost due to land use conflicts, however, most of the resource loss has been small. Land use conflicts and phosphate mining are reconcilable and considerable progress toward their maximum and multiple use of land and mineral resources can be resolved through farsighted planning based on factual data.

Jan 1, 1972

By Alex Rown

"THE SYDNEY COAL FIELD has long been afflicted by high costs and low productivities. However, a distinct possibility now exists that improvements can be made in costs, productivities and revenues. If these hopes materialize, the Sydney coal field will once again be regarded as a valuable asset in our national inventory of energy and metallurgical coals. The economic possibilities for the Sydney collieries depend on performance at the pits and in the market place. Because this audience is already well informed about colliery planning, I would like to start with an assessment of the modern coal market insofar as it may relate to the Sydney field. Since 1950 we have seen a vast growth in the population and industrial empires of the western world which has resulted in an enormous and escalating demand for energy. If the energy supply pattern of the first 50 years of this century had been followed, this would have led to an immense demand for coal."

Jan 1, 1972

By Martin H. Stanczyk

The Organic Act of 1910 established the Bureau of Mines and gave it authority and responsibility for conducting research on separation, recovery, and recycling of waste products and scrap generated by the mineral and metals industries and the consuming public.(1)1 It was apparent to our Nation's leaders even then that mineral resources, once mined, are irreplaceable and that the development of methods for recycling the values contained in wastes would be required to solve the problem of even¬tual scarcity, Estimates of the increase in per capita consumption of mineral resources in this country indicate that the consumption of metals, minerals, and fossil fuels by 1980 will be double that consumed in 1970 (2). The United States can expect to meet its future mineral needs in three basic ways: the first is through increased production of primary raw minerals; second by increasing imports from foreign sources; and third by recycling secondary materials and metals that were formerly discarded as waste. Rather than consider these

Jan 1, 1972

By D. Wallace Fields

Increasing public pressure and demands from various tiers of government have generated a legislative maze of statutory and administrative requirements facing industries involved in mineral extraction and processing. Each tier, of government has asserted concurrent jurisdiction and threats of harsh measures if industry does not satisfy all requirements. In the field of water pollution control, federal requirements have increased, carrying with them increasing techniques of enforcement - ranging from injunctions through criminal penalties. Federal laws have required that states formulate water quality standards as an adjunct to federal regulation. Florida has reacted with the Water Pollution Control Act of 1967. This act incorporates state water quality standards and permit requirements for any installation constituting a potential source of pollution, and provides for civil sanctions as well as injunctive relief. The federal government has utilized an 1899 law to require a permit for discharges into navigable waterbodies - a term which has been judicially defined to include any watercourse capable, after reasonable improvement, for use in the transportation of waterborne traffic. Failure to secure these permits can result in the issuance of an injunction or civil or criminal penalties. The Corps of Engineers will not issue these permits without the approval of the discharge by state, local and other federal agencies. Air pollution similarly is regulated by a multi-tiered network of laws and administrative standards. Federal regulation has increased from early research support in the 1950's through the development of Air Quality Standards and their enforcement by large fines, injunctions, administrative conferences and public hearings. Florida regulation, under the Florida Air Pollution Control Act of 1967, parallels federal law but grants concurrent regulations, requirements and enforcement tools to local and state agencies. Although previous state regulation was minimal, consisting only of three acts passed in 189 1, 1899, and 1911, in the future the mining industry will have to contend with this increasing network of ecological requirements. It is recommended that the industry take the initiative by involving Florida in the Interstate Mining Compact, as well as seeking the passage of a state reclamation law funded by a severance tax.

Jan 1, 1972

By Bruce B. Hanshaw

The Tertiary carbonate aquifer of central Florida is composed of about 2/3 calcite and 1/3 dolomite with minor amounts of quartz and apatite. The Mg content of the calcite is lower in the recharge areas than in the deeper confined parts of the aquifer system. Various geochemical lines of evidence indicate that much of the dolomite is of penecontemporaneous origin but that some may have been formed much later, possibly by ground water. Theoretical studies indicate that the Mg/Ca ratio in solutions is about unity for the three-phase equilibrium, calcite-dolomite-water. Solutions, such as ocean water and some subsurface brines, have Mg/Ca ratios higher than one and should represent dolomitizing solutions. In the areas of principal recharge to the Floridan aquifer, ground water is undersaturated with respect to both calcite and dolomite, and the Mg/Ca ratiois as low as 0.05. As the water moves downgradient, the Mg/Ca ratio systematically increases and approaches unity; saturation of the solution with respect to both calcite and dolomite also increases with length of travel in the system. Thus, in the zone of active potable-water circulation, the chemical process is one of dissolution of minerals until saturation is reached or exceeded. However, in the deeper brackish-water zones that underlie peninsular Florida, dolomite may be forming where the Mg/Ca ratio is greater than one. The necessary Mg may be derived from ocean water or brines recycled through the system as the hydrologic regimen is changed. The driving force may be simple mixing, relative fluctuations of sea level, or a combination of mechanisms.

Jan 1, 1972

By Craig C. Johnson

The purpose of this effort was to investigate the feasibility of employing a piezoelectric transducer for seismic communications applications in mine environments. The transducer, a government furnished device incorporated a high Q, spring-mass resonator to load the air side of the piezoelectric crystal. The resonant frequency was seismic load dependent and fell in the range of 300 to 340 Hz. The effort included a mathematical analysis of the transducer, with corroborative laboratory tests, together with actual communications experiments performed first in an open-formation limestone quarry and finally in an operating iron mine. This work showed that the transducer could be coupled efficiently to hard, competent rock media with power conversion efficiencies of 70 to 80 percent (electrical to mechanical) in typical installations. In the iron mine, when radiating peak power was about 30 W (acoustical) in a gated pulse mode, signals were received at a distance of 760 ft through a massive rhyolite porphyry formation. This represents a 15% radiation efficiency with an input of 200 watts. Despite the high ambient noise level due to operating mine machinery, a signal-to-noise ratio of about 20 dB was achieved using a very narrow band filter to process the received signal, and a data rate of about two pulses/sec was demonstrated.

Jan 1, 1972

By Kenneth N. Weaver

Introduction and Historical Background State Geological Surveys have been deeply involved in industrial minerals from their inception beginning in the first half of the 19th Century. To Massachusetts belongs the credit of having carried out the first Geological survey under state auspices on the Western Hemisphere. One of the causes leading up to this survey was. Governor Lincoln's message to the legislature of May 29, 1830, from which I quote in part: "Much knowledge of the natural history of the country would thus be gained (from a geological survey), and especially the presence of valuable ores, with the localities and extent of quarries and of coal and lime formations, objects of inquiry so essential to internal improvements and the advancement of domestic prosperity, would be discovered.". Similar phraseology is present in practically all of the initial organic acts creating the first State Surveys. High on the list of priorities for these embryo surveys was an inventory of the mineral resources of the State with particular emphasis on the industrial minerals. Prom these early beginnings, the state surveys have developed a great wealth of geological data either directly or indirectly relating to the development of mineral resources. One can gain some conception of the effort that state surveys today place on industrial minerals studies by noting the projects in which they are engaged as reported in the State Geologists Journal. In 1970, for example, approximately

Jan 1, 1972

By John W. Straton

Following the completion of the paper presented in February, 1972, data were received from many other mines and some original respondents submitted more complete questionnaires. The computer program was changed to permit the results to reflect more clearly all the data reported by the mines. The original paper was revised to reflect the new information. There were significant changes in some numerical values, particularly where the size of the sample changed appreciably. Some limited samples considered originally in arriving at conclusions were not relied on in this revision. The revised tables and text are of the same design and format as the original paper.

Jan 1, 1972

By Verne E. Hooker

Stress relief measurements were made at three underground test sites associated with the Henderson project, American Metal Climax, located in the rugged, mountainous region between Loveland Pass and Berthoud Pass on the Continental Divide in Colorado. Sufficient data were obtained to determine the three-dimensional stress ellipsoid for each site. The measurements were made at hole depths greater than one diameter of the mined opening; thus, calculated stresses are representative of premining in situ conditions. The vertical components of stress are in good agreement with overburden depth including the influence of mountain topography. Horizontal components of stress substantially increase with depth. These components are believed to be influenced by stresses presumably of tectonic origin. The largest measured principal stress was 5,900 psi at a depth of 3.708 feet. The predominant orientation of maximum principal stress for the determinations at greatest depth is in the NW-SE quadrants.

Jan 1, 1972

By Robert Stefanko

The Federal Coal Mine Health and Safety Act of 1969 had far reaching effects upon many aspects of mining, ventilation being no exception. In this paper, good ventilation procedures are briefly reviewed, and attention is focused on the changes brought about by the new Act. By way of illustration the ventilation system for a typical Pittsburgh Block system is developed and the requirements of the fan determined. This is then solved by an available computer program, and the application is evaluated. Figure 1 represents a projected system for a coal property 1 by 3 miles in plan at a depth of 1000 feet with a coal thickness of 6 feet and desired daily tonnage of approximately 7200 tons on a two-shift basis. Only one half of the mine is shown (north area) with a mirror image mining arrangement to be developed concurrently for the south area. Six working units are projected, three in each area, one on pillar extraction, another developing panel entries and a third on main entry development. A two-split system is used for each working section so that the continuous miner and bolting crews each have a separate split of air, and no equipment need pass through a line brattice. The old requirement of 6000 cfm at the last open crosscut has been increased to 9000 cfm, and for the first time a minimum quantity (3000 cfm) is stipulated at the face thus requiring either line brattice or an auxiliary fan. With the respirable dust requirement limited to 3 mg/m3, the use of a blower system is precluded and exhaust systems are virtually the only choice. Maintaining the line brattice within 10 feet of the working face at all times as required by the new law has a definite effect on the mining cycle and is most difficult at best. In the highly gaseous Pittsburgh seam located in south-western Pennsylvania and northern West Virginia quantities of 20,000 cfm per split are not uncommon to maintain the methane percentage below the required l%

Jan 1, 1972

By Fraser RJ

A Robbins Raise Drill Model 61R was used to provide one 7' diameter shaft 1050' deep in Clutha Development's exploratory mine at Blackwater in Central Queensland and two 7' diameter shafts 1450' deep at their South Clifton mine on the Illawarra Coast of New South Wales.

Jan 1, 1972

By James C. Gilliand

Leo-potpourri, was selected as the title to this paper for several reasons. First, it is a fascinating word--not looking like it sounds or sounding like it looks. It also allows for a great degree of flexibility in designing a presentation around it. Further, it has become popular to use this eco hyphen something pattern. We hear of eco-mania, eco-hysteria and the like. Lastly, in this era of intense environmental concern, two of the principle elements on which the integrity of our efforts must be equated are ecology and economics. Accordingly, the term "Eco-potpourris" allows me to roam at will through the great number of considerations that make up this environmental issue. Whereas only a few years ago the subject of environment and environmental control had low visibility with the public, today it competes as the focus of attention with the many other popular social issues of our time. The program content here at this meeting, for example, is liberally represented by papers dealing with one or more aspects of environmental concern. If one would look at the 1964 program, in contrast, I would expect that no more than possibly one or two papers covered this subject and even then that those papers dealt principally with the environmental aspect of occupational health. It is gratifying that the program at this meeting demonstrates a serious awareness to a broad spectrum of environmental concerns. It would be a mistake, of course, to believe that this clamor for a quality environment is a "flash in the pan" that will soon subside. The general public has been thoroughly aroused and even frightened into

Jan 1, 1972