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By John J. Peregoy, James E. Downes

INTRODUCTION The U.S. Department of Energy's Waste Isolation Pilot Plant (WIPP) is being constructed to provide permanent storage of radioactive TRU waste materials emanating from military weapons production. These wastes are contaminated with radioactive elements heavier than uranium, thus the name trans-(or beyond) uranic (Uranium wastes). The WIPP site, which is located 26 miles east of Carlsbad, New Mexico, was chosen thru a selection process after the National Academy of Sciences recommended salt deposits as a promising host strata for the storage of radioactive wastes. Throughout the United States numerous DOE facilities have produced and stored defense-generated TRU wastes. Once WIPP becomes operational in the fall of 1989, all sites may ship directly to this repository. A companion project has developed special shipping containers (TRUPACT) for safe transport of materials to WIPP. The WIPP facility is currently composed of surface buildings, three shafts, and underground storage and experimental rooms and tunnels. Frontier-Kemper Constructors, Inc. (FKCI) has nearly completed the construction of the fourth shaft, an intake shaft, to provide additional ventilation to the underground workings. PLANNED SHAFT EXCAVATION METHOD Full-face raise boring ( upreaming ) was the allowable method selected by Frontier-Kemper Constructors for the excavation of the shaft. After arrival of an oil-field type rotary drill rig in December 1987, a 9 inch diameter pilot hole was drilled from the surface to the mine level, a depth of approximately 2145 feet.

Jan 1, 1989

By Charles H. Dowding

INTRODUCTION "On many projects, the tendency is to drop interest and support of the geological service as soon as it seems safe. That . . . is a short-sighted policy . . . It would be of further service perhaps to learn whether predictions were reasonably true to life." --C.P. Berkey, 1938 (3) This paper quantitatively compares predicted and encountered shear zone size and location and rock type for tunnels in the Colorado Mineral Belt. The Colarado Mineral Belt is composed of igneous formations with associated metamorphic rocks and faulting. As such, it represents the most complex of provinces for at-grade predictions (27). Shear zone and rock type data are assumed to be statistically homogeneous because of the common geology of the seven tunnels. It is often felt by geologists and engineers that the amount of information from which a geological model is created is so low that any statistical inferences are unstable. In other words, the addition of new data may drastically alter the means and variances suggested by the model. Therefore, predictions are rarely couched in quantitative statistical terms but modified with "probably," "most likely" or "possibly." Comparison of predicted and encountered data from past geological models will permit the "probably's" to be quantified and distilled from the art of geological prediction. To date, two other studies of the validity of predictions have been made (26 and 16). Together, these two studies indicate that

Jan 1, 1976

By Thomas D. Boyce

Minewater from many western U.S. uranium mines often contains radioisotopes in concentrations higher than permissible for discharge to unrestricted areas. .Radium 226 has the lowest permissible concentrations of all radioisotopes and usually greatly exceeds this limit in untreated effluents. This radionuclide is derived from the natural radioactive decay of uranium: [ ] The treating of minewater effluents has been studied previously (1) and the classical removal method for radium has been adsorption on barytes or freshly precipitated barium sulfate. This paper describes the removal of radium from minewater by utilizing a selective complexer based on a crosslinked organic polymer matrix.

Jan 1, 1982

By J. R. Boldt, C. M. Kleemann, V. N. Mackiw, B. Meddings, J. A. MacLellan, E. J. Maney, D. E. Halter, D. J. I. Evans, J. Honkasalo, M. F. Dufour

The technology employed in the processing of nickel- and cobalt¬bearing ores is a continually developing process for utilizing the natu¬ral resources available at a given time. Most of the nickel-bearing ores of commercial importance fall under the category of sulfide or lateritic ores. While the occurrences of both types of ore have been known for over a century, until 1960 sulfide ores largely from Cana¬dian mines have constituted the chief source of production for com¬mercial nickel in the Free World. Sulfide ores are readily amenable to some physical means of concentration, but the lateritic ores are not readily concentrated, and to compete economically with the sulfide ores only the high-grade garnierite ores (a type of lateritic ore) found in New Caledonia were processed to any great extent up to the time of World War II. Around 1960, a gradual shift in emphasis towards latetitic ores as a commercial source of nickel became evident. See Fig. 1. New discoveries of sulfide ores, usually located underground, had not kept pace with the steadily increasing demand for nickel. The lateritic ores, found near the surface of the earth, could be readily surveyed and mined. Lower cost processes were being developed for the extrac¬tion of nickel from lateritic ores and for a time it appeared that, based on pre-OPEC economics, the lower grade lateritic ores-down to 1.2% nickel-could satisfy an increasing share of the world demand for nickel. The sharp increase in the price of crude oil in the 1970s, however, slapped an economic damper on the lateritic ores. Processes for treat¬ing lateritic ores consume large amounts of energy; as the nickel industry entered its deep recessionary period in 1981-83, nickel pro¬duction from lateritic ores became less and less profitable than from sulfide ores. At the same time, new sulfide ores were discovered and brought into production, notably in Australia and South Africa. The chapters in Section 17 were prepared in 1973. Recent improvements in mineral dressing techniques since then include Inco's pyrrhotite separation process which can remove additional pyrrhotite from nickel concentrates, resulting in reduced sulfur dioxide emission from the Sudbury smelter, by some 25%. The chapters in this section dealing with nickel are grouped in line with the two broad categories of nickel ores. Starting with the description of nickel and cobalt ores in Chapter 2, Chapter 3 deals with the processing of sulfide ores, and Chapter 4 deals largely with lateritic ores. The intermediate steps to produce a suitable feed for extraction plants and refineries are similar in principle within the same categories, although dissimilar between sulfide and lateritic ores. Thus Inco in Canada employs flotation and so does Western Mining Corp. in Australia, although Inco's plants were started before World War II, and that of Western Mining only recently in the late 1960s. Treatment subsequent to the ore dressing step, however, shows some interesting differences. The earlier parts deal mostly with established and conventional practices, leaning heavily on pyrometallurgy in both

Jan 1, 1985

By Walid M. Abdellah, Soliman Abu Elatta A. Mahmoud, Hanaa A. Abu Khoziem

The high-grade Th-U-Y zone is one of the numerous mineralized zones found in the El Garra El Hamra hydrothermally altered syenites in southwestern Egypt. It is characterized by the thorium minerals thorite and thorogummite, which are closely associated with xenotime-(Y). This zone of mineralization is localized in the eastern part of the El Garra El Hamra hydrothermally altered syenites. This zone does not relate to the first phase of syenites that appeared on the surface but is linked to the other, hidden phase of the syenitic body. Additionally, the fluids responsible for the mineralization of this zone belong to the late-stage hydrothermal event as well as the fault action due to the fact that it had continued reactivations for a long period of time. The studied mineralized zone also contains ceriopyrochlore-(Ce),(Ce,Ca,)2 (Nb,Ta)2O6 (OH), fluorite (CaF2) and barite (BaSO4), which are found in considerable amounts, whereas apatite (Ca5(PO4)3F) and chromite (FeCr2O4) are rarely found together with Fe-oxi-hydroxides (hematite and goethite) with a minor amount of jarosite (KFe33+(OH)6(SO4)2). Finally, the main constituent mineral in the zone is the pseudomorph perthite in addition to quartz, which is found as deformed crystals. A technological sample was collected from this zone and was found to assay 4.62 weight percent thorium (Th), 0.37 weight percent uranium (U) and 3.12 weight percent rare earth elements (REEs). From the chemical and mineralogical composition of the studied technological sample, the leachabilities of Th, U and REEs were investigated using sulfuric acid (H2SO4) agitation leaching and pug leaching methods. The latter was found to be preferred under the conditions of 0.54 ton H2SO4 per ton of altered syenite at 110 °C for two hours.

By R. Bhaskar

The control of quartz levels in the respirable dust requires an approach different from that used to control respirable coal dust. The unique physical properties of quartz have to be utilized when developing quartz dust control systems. Also, techniques that modify the surface properties of quartz dust so that conventional dust control measures are effective should be explored. For instance, the wetting characteristics of quartz can be modified so that the capture efficiency of the quartz dust can be improved. Foam sprays assist in modifying surface wetting characteristics. This paper summarizes the results of a study that was conducted in an operating mine to evaluate the effectiveness of a compressed air foam spray system installed under the boom of a continuous miner and directed so as to cover the pan and the gathering arm. The objectives of the study were to evaluate the effect of the foam underboom sprays on (1) the respirable dust concentration in the ambient air, (2) the quartz concentration in the respirable dust. The engineering design of the foam generation and delivery system is described in the paper, followed by a description of the mine and the dust sampling strategy. The data were analyzed to study the effect of foam on respirable dust and quartz concentrations at the miner cab, face return and the intake. The results of the data analyses and costs are presented in the paper.

Jan 1, 1991

By August E. Vandale

I speak to you today on the subject assigned to me, "Subsidence - a Real or Imaginary Problem", as a representative of Consolidation Coal Company (a wholly owned subsidiary of Continental Oil Company). The information I relate to you is our experience in the Pittsburgh Coal Company Division of Consol and covers the Pennsylvania properties and mines with particular emphasis on the mines in the south- western portion of the State or in the immediate vicinity of Pittsburgh, Pa. Mining of Freeport and Pittsburgh seams of coal in the Pittsburgh vicinity dates back over one hundred years. Consol, or its predecessor, Pittsburgh Coal Company, has been actively engaged in mining in the area since Pittsburgh Coal Company was organized in 1900. Pittsburgh, Pennsylvania came into prominence as the Steel City largely because of the vast reserves of high grade metallurgical coal readily available in the immediate vicinity and also because of its favorable river transportation. Early in the 1900's we operated over 100 small coal mines, with operations located in the Counties of Allegheny, Fayette, Washington, Westmoreland. We have also operated mines in Somerset and Greene Counties. Titles in Pennsylvania can be in three estates: (1) title in fee, (2) title to the mineral, (3) mining rights permitting the removal and extraction of the mineral with or without waiver of surface damage. Consol has over the years acquired good legal title to the coal lands purchased from individual farm owners, with good broad mining rights, and in 98% or more of its title has a complete waiver of surface damage or the right to subside the surface land. In the early days of our Company, individual coal farms were purchased from land owners. Many of these titles severed the coal estate from the in fee title and good mining rights with waiver of surface were conveyed in the original severance deed. Thus, minable coal reserves were put together by the purchase of the coal under many individual farms in an area. In the early years, the mines practiced hand dug mining - later going to mechanical cutting with hand loading of the coal. Systems used were entry driving with room and rib panels. We have practiced full recovery mining as far as practical during the years of hand loading, as well as in the later years when the mines were mechanized. Mining system layouts, methods and procedures have changed from time to time to keep pace with improved mining machinery and new inovations, such as roof bolting and rubber tired haulage.

Jan 1, 1967

By Jack E. Bailey

From a start in 1957, milling 3,000 TPD of copper ore, the Cyprus Pima Mining Company, which is located 20 miles south of Tucson, has expanded its operations four times, and is currently treating over 55,000 TPD of ore.1 The most recent expansion added a 14,000 TPD semi-autogenous concentrator to the operation. Shortly after startup in January, 1972, the semi -autogenous plant exceeded the designed tonnage rate.2 Ore from the mine is delivered to a 54 inch gyratory crusher and is reduced to a minus 8 inch product. From the crusher the ore is stacked on a surge pile and then reclaimed and fed to the two parallel grinding circuits. A 28 ft. diameter by 12 ft. long semi-autogenous mill and a 16.5 ft. diameter by 19 ft. long ball mill make up each grinding circuit. The semi-autogenous mills are in closed circuit with screens and the ball mill circuits are closed with hydro- cyclones. Rougher flotation follows the grinding operation. Concentrate regrinding and cleaner flotation is performed in Mill I, the older mill. The generalized flowsheet is shown in Figure 1.

Jan 1, 1975

By Frank L. Gaddy

Falls of roof account for over 50% of the fatalities that occur in coal mines in the US. Thus, roof control is one of the more important phases of underground mining. In reality, the control of roof influences the system of mining and is a major determinant of the width and spacing of working places, operations at the mining face, ventilation control, and surface subsidence. Frequently, the control of roof is the largest single cost item. Roof control is a never-ending task, not only at the working face and throughout sections where men are working, but along haulways and air- ways that must be maintained for the life of the mine. This is because roof, even the best of roof, slowly deteriorates, so it must be frequently examined, with corrective support applied when needed. As coal is excavated, stresses are set up in the roof because the previous equilibrium is upset, resulting in pressures that cause fractures and slight movements that are frequently hard to detect. Unless the immediate roof, in the excavated area, is given support by artificial means, it might fall or there might be a succession of falls, varying from a thin scale to several feet, depending on the nature of the top. Exceptions to this are those rare mines, or sections of mines, with hard, strong, nonweathering roof that requires no support.

Jan 1, 1981

By J. B. Fletcher

Miami Copper Company has used conveyor belts underground since 1947, At that time, the draw level for a portion of the orebody was only 25 feet above the haulage level To get the main haulage drifts as far away as practical from under the stoping area, 301, belt conveyors were used for lateral transfer, If the haulage drift was kept in good ground., a satisfactory draw of these stopes could be effected in that repairs to the conveyor drifts could be accomplished while drawing ore from the stopes. Some 7,400,000 tons of ore were mined with the 301d belt conveyor at a belt cost of approximately $0,004 per ton of ore. When the mining plan for a new section of the mine was laid. out in 1953, it was decided to use belts to collect the ore from the higher draw levels, and. move the ore laterally to centrally located concrete ore passes for transfer to the main haulage level (See Cut #1), The final plans used belt conveyors too collect from 3 stopes: on the 570 level, 2 stopes on the 720 level, and one stope on the 900 level. The six stopes to be mined in this manner would produce about 8 million tons of ore, and the sequence of mining was such that not more than four 400 feet conveyors would be in use at one time, Four conveyors using 36 inch, 4 ply belting were designed by the mine engineering office and fabricated at the mine shop, so that no piece was longer than 10 feet, and. the heaviest piece was the 25 horsepower motor, The head drive section, and the tail-pulley-takeup section were of bolted construction so they could be broken down for easing moving, Due to the size of the mine openings, the belt had to be transported into the mine in 400 feet rolls, requiring two splices for an installed belt. A torque arm speed reducer was used with a V -belt drive which made it possible to change the speed of the conveyor by changing the diameter of the V-belt pulley (See Cut #2).

Jan 1, 1958

By L. G. Austin

A simple finite difference algorithm has been used to compute a simulation model for unsteady-state ball milling. The model considers the mill to act as if it were three fully-mixed reactors in series (one-large/two- small), it incorporates the-Rogers-Austin mass transfer law relating mill hold-up to flow rate through the mill, and it allows for the reduction in breakage rates caused by over-filling of the mill at high flow rates. The computation is rapid and requires only small storage space. Examples are given of use of the model.

Jan 1, 1984

By Victor M. Mercado, Jay B. Shah

Spalding DeDecker Associates, Inc. (SDA) designed a tunnel project that fulfilled the Sustainability Objectives of Social Equity, Environment, and Economics. The project translated the principles of Sustainable Development into actions that lessened the impacts of construction on environment, lives of residents, businesses, traffic, and other social systems (i.e., shopping, recreational, and educational). The project involved the construction of a 16,108 feet of 84 inch diameter sanitary sewer interceptor by tunneling 40 feet beneath the ground surface through difficult geological and hydrogeological settings. An effective public information and stakeholders relationship program was developed to achieve the stated objectives of sustainability.

Jan 1, 2003

By M. Buxton

"Advanced data acquisition and process modelling technology provides online data and decision support about different aspects of the resource extraction process. Real-time approaches have recently been applied to utilize the value of this information for improved production control in mineral resource extraction in different operational set ups including coal, polymetallic ore and gold deposits. The key concept of these approaches promotes the change in paradigm from discontinuous intermittent process monitoring to a continuous process and quality management system in the resource extraction process. The framework includes a real-time feedback control loop that rapidly links online material characteristics data acquired during extraction at the mining face, during material handling and processing with a sequentially up-datable resource model. This will allow near real-time optimization of decisions related to long-term planning, short-term sequencing and production control. The contribution reviews recent developments in the three main constituents sensor based material characterisation, rapid updating of grade control models and simulation based optimization for improved production control. Technological readiness is assessed and critical gaps for further technology development are identified. The value added is illustrated by means of selected case studies. INTRODUCTION With the depletion of known and established mineral reserves, the decrease in head grades and the continuing demand of mineral raw materials by the modern society, future exploitation will move towards extraction of deposits under geologically more complex conditions. Complex deposits are characterized by a low continuity in grade, presence of deleterious elements such as arsenic and high irregularity in the geometry of the ore boundaries. The profitable exploitation of such deposits becomes significantly more challenging. To be able to better utilize such unconventional mineral resources of the future, smart autonomous mining systems are needed, which integrate local exploration of spatially varying material characteristics in–situ and have the ability to follow and extract the pay zones in the ore body while minimizing dilution (Buxton and Benndorf, 2013). The main barriers to overcome for the successful economic exploitation are: • effective grade control which will maximize resource potential along the whole value chain, • minimization of handling zero-value material introduced by dilution, thus • reducing unnecessary expenditure of energy and financial resources and • management and control of the geological uncertainty due to limited information available,"

Jan 1, 2017

By Douglas R. Cook

Our present and future needs for base and previous metals are not satisfied by the present rate of new viable discoveries. This deficiency can be met by increasing the number of competent exploration organizations and by doing a more effective job of prospecting. My principal purpose is to show that new discoveries can be increased by improving the use of exploration techniques in a concept-oriented exploration program. Exploration techniques are defined and classified. The effectiveness of many exploration groups can be improved by better definition of objectives and thorough planning of the exploration program. The role of objectives, planning, and the use of techniques are discussed within the scope of the exploration framework. Common pitfalls in the use of exploration data are identified such as: inconsistency of geologic measurements, negative use of data, indiscriminate use of geo-surveys, collection of irrelevant information, and the unrealistic desire for exploration panaceas. Suggestions for improving the use of techniques include the use of multiple-working hypotheses, improvements in the quality of exploration data, use of geology in the selection, planning and interpretation of geochemical and geophysical surveys, and the recognition of variables and limitations affecting the interpretation of exploration data. The critical role of geologic mapping by Federal and State agencies is mentioned for satisfying the continual exploration demand for better geologic maps and filling many gaps that currently exist. The importance of imaginative and qualified exploration personnel is discussed as well as the maximum utilization of their exploration creativity. The problem of integrating field studies, research and training at universities and research institutions is identified. The need for high-quality research in economic geology is emphasized especially the importance of reducing the steadily increasing gap between basic and applied research.

Jan 1, 1968

By William B. Schmidt

In July of 1974 a study team comprised of the authors was formed by the Department of the Interior. It was supported in part by funding from the National Science Foundation. The purpose of this study group was to visit coal mines and research and manufacturing facilities in England and Germany, to review the status of mining in these countries, and to identify mining technology which might have application to U. S. mining conditions. The duration of the visit was 18 days. The first week of the trip was spent in England. Time does not permit a complete recitation of the team's impressions but a few of the more interesting technologic developments will be discussed. These fall into the following categories- High Speed Development Ground Support Chainless Haulage and Face Conveyors Nucleonic Steering of Shearers Miscellaneous

Jan 1, 1975

By S. J. Lefond

Most people, when Borates are mentioned, mentally visualize the famous twenty mule team (really eighteen mules and two horses), trudging across the Mojave Desert or "she burns green Rosie, we are rich." Actually, however, the first use of borax was prior to Babylonian times. Their emissaries had orders to bring borax Iron the Gobi desert for use as a flux by the Babylonian goldsmiths. The borate mineral imported for this is not known but probably was borax. The ancient Persians and Arabians knew about borax and the Arabic word "Baurach" appears in a two thousand year old manuscript. The Sanscrit word for borax was tincana which has been corrupted to tincal. The Chinese were using borax as a glaze in three-hundred B.C. Marco Polo brought the first borax, along with gunpowder and spaghetti, from Mongolia to Europe in the late 1300's. Borax from Tibet was imported to Europe for nearly 500 years. In 1772 boric acid (sassolite) was discovered around Tuscany, Italy as a precipitant from volcanic steam vents. Production of boric acid started there about 1815 and provided the sole competition to the borax from Tibet. Borate deposits in Turkey have been known and exploited on a small scale since the 13th century. It is only recently that the operations are being modernized and production increased. About 1836, borax minerals were found in Chile and Argentina with borax production starting in 1852 in Chile and in Argentina in 1886. During the latter half of the 19th Century, Chile was the principle world producer of borax.

Jan 1, 1980

By D. W. Park

Longwall Strata Control and Maintenance System (LoSCoMS) is a software and data communication system developed at the University of Alabama. This system integrates real-time shield monitoring, data presentation, analysis and forecasting of forthcoming events. The main objective of this system is to provide stability information on longwall panels including excessive shield load, low setting pressure, leg leakage and poor shield performance, eminent maintenance problems, etc. Analyses of various mining and geological parameters were also performed to determine past and present roof characteristics and to forecast roof loading patterns for the following mining cycles, next periodic weighting, etc. A local coal mine in the Warrior Coal Basin has adopted this system to provide daily evaluation of ground stability and maintenance problems of their longwall panels. Two years of experience with this system is covered in this paper.

Jan 1, 1998

By Daryl R. Tweeton

Bureau of Mines research in in situ uranium leaching includes injection well construction and environmental aspects. Clogging of injection wells is a common problem, and is affected by construction techniques. Part of the clogging can be caused by a low-permeability skin left on the borehole wall if the drilling fluids are not thoroughly flushed out. Certain polymer drilling fluids are less prone to cause clogging than bentonite muds, since a lower solids content can be used. The environmental research primarily involves two contracts. The first describes the environmental impact of in situ leaching and the effect of environmental legislation on leaching; the second describes the cost effectiveness of various methods of restoring ground water quality.

Jan 1, 1978

By G. Bitsianes

An experimental procedure was developed for studying magnetic roasting on a accurately-controlled laboratory scale. The loss-in-weight method was used and the course of reduction could be followed under a reducing gas atmosphere containing as many as five different components. Some important variables of the operation were checked on a marginal Mesabi iron ore containing porous and dense varieties of hematite as well as pure goethite. The conditions simulated were those for the grate roasting of a coarsely-sized ore burden. Temperature was maintained at 600°C; gas composition at 4.25% CO, 4.25% H2, 17.0% CO2, 15.0% H20, and 59.5% N2,, and gas flow rate at about 1,5 lineal feet per minute. The ore charge was composed of quarter-inch cubes. Under these conditions, the ore porosity was found to be one of the governing variables of the operation. Results showed that an ore size limitation existed as a function of this ore porosity. For efficient magnetic conversion, the size limit was 3/8 inch for very porous ores and about 65 mesh for very dense ores. An anomaly was noted in the weight losses incurred during actual magnetic conversion. For goethitic ores, these were generally about 13 per cent higher than could be accounted for theoretically. The effect was attributed to possible non-stoichiometric structures forming during the reduction process.

Jan 1, 1960

By T. J. Lien

AMAX Coal Company's Belle Ayr coal dryer is the first industry attempt to commercialize sub-bituminous coal drying which has been the subject of laboratory and pilot plant tests for almost two decades. This paper presents the historical background, construction, start-up and operation of this adaption of fluidized bed coal drying technology to Powder River Basin coal. The flowsheet and operational problems encountered during plant start-up are discussed together with general material balance and product quality.

Jan 1, 1990