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By Robert J. Rothwell

Underground mining of coal by longwall mining methods has not been a predominant technique in Ohio. To date, only five mines in the state utilize this method, however, the technique has sparked a certain amount of controversy. As a mining technique, longwalling was introduced into southeastern Ohio in the early 1970's but it did not attract public attention until the mines began moving into privately held surface lands. This occurred coincidentally at about the same time that the state of Ohio began to regulate the environmental impacts of underground mining. Prior to the passage of the Surface Mining Control and Reclamation Act in 1977, (SMCRA), Ohio's reclamation law, Chapter 1513 Ohio Revised Code (O.R.C. 1513) did not regulate underground coal mines. As a result of SMCRA, the Ohio Statute was amended in 1978, to include regulation of the surface effects of subsidence. The inevitable result was that existing mines were immediately subject to regulations that were not considered during the initial mine planning process. (For an excellent survey of Ohio Laws that deal with coal mine subsidence, see Zima, 1985. ) The problem faced at that time by both the coal industry and the Ohio Division of Reclamation (the agency within ODNR charged with implementing O.R.C. Ch. 1513.1, was that of attempting to superimpose permitting requirements, and design performance standards onto mines that' had been operational for a number of years.

Jan 1, 1986

By Dr. David R. Hargis

Finite-difference digital computer models can be used to evaluate the effects of proposed mine dewatering and depressuring operations on ground-water aquifer systems. The effects of proposed dewatering and depressuring operations can be simulated for both underground and open-pit mining in confined and unconfined aquifer systems. Design of dewatering and depressuring well arrays to accommodate proposed mining operations in a variety of hydrogeologic settings can be accomplished through judicious application of well-documented and tested computer programs that are widely available from government agencies and universities. The speed and flexibility of the computer models can provide an economical means for comparison of alternative mining plans, and can be used to determine the optimum mine plan with respect to dewatering requirements.

Jan 1, 1980

By Robert W. Holliday

Natural resources are the reservoir from which society draws its material sustenance. Although there is a growing awareness of the need for aesthetic resources such as space for recreation and natural beauty, the basic resources are soil, air, water, and minerals including fuel. Minera's and all sources of energy gain in relative importance with advancing technology and expanding industrilization. In the highly industrialized economy of the United States, almost every aspect of man's life is touched in some way by a product of, the mineral; industries. Agriculture owes much of its productivity to mineral-based fertilizers, insecticides, and mechanical equipment. Modern construction, manufacturing, communications, and transportation are all dependent on nonmetallic minerals, metals, and fuels. Throughout history, those nations with access to minerals, and the technology for using them, have gained ascendency. Before World War II the leading powers also were, leading coal producers. In order of declining rank the five leading' coal producers were the United States, the United Kingdom, Germany, the USSR, and Japan. That the military victory went to the side with the greater' capacity to convert iron and coal into tools of industry, and weapons, is' more than coincidence. It is a fundamental' fact of existence. It is axiomatic that the United States must have a continually increasing supply of minerals if we are to meet the needs of our burgeoning population for a comfortable standard of living and for national security.

Jan 1, 1968

By Brian E. Davies, Bobby G. Wixson

INTRODUCTION The mining, extraction and refining of metals into useful materials is an honorable profession with an ancient and productive history. Civilizations have long depended upon metals for their implements, structures and machinery necessary for survival, growth, and development. Today, as in the future, metals and minerals are essential to the progress of mankind as we approach the 21st century with technologies and concepts that will require new concepts and production from the metal mining and processing industries. Today is the tomorrow we talked about yesterday and the implementation of new ideas is essential if we are to achieve "Frontier Technology in Mineral Processing". Unfortunately, the state-of-the-art mining, processing, smelting and refining methods historically employed were less than desirable environmentally, which has caused todays public to view the metal mining and processing industry with concern. Presently the ancient rock and chat tips connected with old Roman lead-zinc mines which were worked in Wales are causing stream contamination problems that must be corrected at considerable expense to the local governmental agencies (Firth, J.N.M., et al., 1981). However, improved progress has been made and the environmental control and clean-up procedures utilized by modern lead-zinc operations in the "Viburnum Trend" or "New Lead Belt" of South East Missouri may serve as a model to illustrate how alternative technologies, environmental concerns and cooperative efforts contribute to efficient mineral production within the confines of a U.S. National Forest region without significant environmental impacts. This area received international attention when it was opened within the boundaries of the Clark National Forest in the mid 1960's. By 1970 it ranked first in the world by producing 432,576 short tons of lead ore and has since continued in this position producing 451,153 short tons of lead ore in 1983 representing 91% of the total United States lead production (U.S. Bureau of idines, 1983). This production comes from a mining area approximately 40 miles long by 10 miles wide extending in a north-south direction. Geologically the lead is disseminated throughout the Cambrain age Bonneterre Formation, mostly a dolomite, at depths ranging from 700 to 1200 ft. (213.4 to 365.8 m). Galena (lead) is the principal ore mined with lesser quantities of sphalerite (zinc), chaleopyrite (copper) and silver being recovered as economic co-products. This new mining development in one of Missouri is most scenic areas could have led to a classic confrontation between industries and environmentalists. Instead, through the cooperation of industries, governmental agencies and university researchers, the Ozark environment has been protected, and may serve as a model for future coexistence of the mineral industry with the environment. Cooperative Program Development As early as 1965 five new mines and two lead smelters were being prepared for production and environmental concern was an essential part of that planning. All the mining companies became acquainted with representatives of the various federal and state agencies and scientists from the University of Missouri-Rolla (UMR). During the next six years, St. Joe Minerals Corporation, American Metal Climax, Inc., Cominco American Incorporated, Ozark Lead Company (Kennecott) and American Smelting and Refining Company participated in cooperative research efforts. The companies also participated in information exchange meetings, the development of improved analytical methods and the utilization of research findings in the modification or construction of pollution-abatement facilities. Early on research was carried out to determine background values and to establish natural baselines of trace metals in the surrounding environment. The unusual topography and drainage pattern of the mining area were helpful since it was possible to establish control sites and test sites below individual mine-mill operations to study waste-water effects on the receiving streams. The location of the ‘New Lead Belt', mines, mills,

Jan 1, 1985

By G. R. Marchant

The nonferrous industry has for many years maintained monitoring stations in agricultural areas in the vicinity of smelters to collect data concerning impact of smelter emission on agricultural crop production (Thomas and Cross, 1928). However, in 1967, the United States Congress passed the Clean Air Act which was amended in 1970 (Marchant, et al., 1977). The interpretation of this act by the Environmental Protection Agency (EPA) made it necessary for the industry to install extensive real-time ambient sulfur dioxide (SO,) monitoring systems. This was only the tip of the iceberg. Since that time as a result of additional laws and agency directives, it is now necessary to monitor concentrations of a number of substances -in both air and water. And unless there is a major change in government thinking, this trend will continue during the decade of the eighties. It is difficult to estimate the full impact of these laws. Nevertheless, the impact is large and affects every person in the United States today (Anon., 1972; Rockefeller, 1971; Nelson, Yeager, and Guptill, 1973; and Anon., 1975). It prohibits the burning of trash and paper in most areas of the country. It increases the cost of transportation and the price of motor vehicles. It increases the, cost of nearly everything that is manufactured. In industries which compete in the international market, it reduces their competitive position. In some industries the environmental impact is felt on costs of goods sold in the vicinity of 25% of the total production costs. The major portion of these costs is not due to the monitoring systems but instead is due to the increased cost of production facilities, equipment, and raw materials in industries that are required to comply with environmental regulations.

Jan 1, 1979

By Roy M. Fleming

During the decade of the 1970's, a new emphasis was placed on assuring a safe and healthful workplace for all American workers. Much of the basis for this national effort was federal legislation: the Occupational Safety and Health Act of 1970 and the Federal Mine Safety and Health Act of 1977 (amended from the 1969 Coal Mine Act). One of the agencies involved in this protection effort is the National Institute for Occupational Safety and Health (NIOSH) of the Centers for Disease Control (CDC) in the Department of Health and Human Services (DHHS). In fulfilling its mandates under the 1970 and 1977 Acts, NIOSH conducts research, experiments, and demonstrations to support and stimulate advancements in health and safety practices. Priorities for NIOSH research are established primarily through congressional mandates, requests from the Department of Labor, needs as defined by NIOSH researchers, and surveillance information. Emphasis is placed on research in the areas of toxicology, industrial hygiene, physical and chemical sciences, physiology, ergonomics, engineering, psychology (behavior and motivation), and epidemiology (industry-wide studies). The framework of the current Institute program to identify, evaluate, and control occupational hazards includes activities in surveillance, research, evaluation, and training. These activities are planned and evaluated through a system that coordinates the efforts of eight research and scientific divisions. Each division develops projects to address program areas that have been identified by NIOSH management as having highest priority. In surveillance programs, the objectives are to identify substances and agents found in a representative sample of workplaces and to collect and evaluate information on rates of disease and injury in occupational groups. Information is also collected on occupational safety and health programs implemented by industry. Estimates of worker exposures and the potential for adverse health effects are considered in setting priorities for further investigations. A related activity, which also serves to provide technical assistance to industry, is NIOSH's Health Hazard Evaluation program. On-site investigations of workplaces are made in response to worker, employer, or government agency requests. Both industrial hygiene and medical examinations are conducted, and the results contribute to identifying new problems and evaluating their significance which may have public health implications beyond the particular worksites that are investigated. Field and laboratory research projects are performed to meet several objectives: - Characterize the working environment by evaluating current and past exposure levels for workers who are included in epidemiological or medical investigations. - Develop epidemiological information to define the association between the substance or agent under investigation and the acute and chronic health effects on workers. - Determine through animal studies the parameters of an association between exposure and effect. - Investigate the etiology of disease. - Develop sampling and analytical instruments and techniques and demonstrate their application for measuring toxic materials in the workplace. - Formulate sampling strategies that will accurately and precisely indicate exposure levels. - Develop medical procedures to prevent disease and to detect the presence of disease and early indicators of disease. - Assess the technology for control of exposures, including engineering and administrative techniques, personal protective equipment, and work practices. Presently, the research program is focused on reproductive effects, neurotoxic effects, injury/trauma, lung disorders, cutaneous disorders, cardiovascular disorders, cancer, stress-related disorders, effects of physical agents, digestive disorders, and renal and other organic disorders. In studying these issues, priorities are determined by the seriousness of possible adverse health effects resulting from occupational exposures, the feasibility of studying existing records or obtaining new data, and the size of the population which is potentially affected. Where there is low level of suspicion concerning adverse health effects or where an occupational disease occurs in a variety of industrial environments, investigations are limited to gross analyses of health effects such as review of mortality patterns. In such studies, the industrial populations selected are those for which existing data resources can be utilized. Such data consists of records of occupational exposures or health status which have been maintained by the employer, the union, or Government agencies. Where a review of the available information suggests that serious health hazards exist and the existing data resources are inadequate for quantifying the relationship between the specific biological response and type and degree of exposure, prospective studies are initiated. Information derived from such research is essential for the development of sound criteria for control of industrial exposures to noxious agents. Other input to the criteria documentation process comes from searching and evaluating the literature. Criteria documents contain the recommendation of an environmental limit where information is available to support it, as well as the recommendation of work practice controls, medical evaluation, information for workers to recognize and avoid the hazard, and identification of specific research gaps. In some cases, during the criteria document preparation, gaps in knowledge are found which necessitate further research before an occupational standard can be recommended.

Jan 1, 1981

By Kwangmin Kim, Junnhyeok Park, Taehee Lee, Minkyu Kim

Mine tailings storage facilities (TSFs) can be a significant source of fine, respirable dust. This dust poses concerns, especially for nearby communities, because of its detrimental impact on respiratory health. To address these concerns, this study examined the effectiveness of commercially available polymers, known for their biocompatible and environmentally friendly features, to prevent dust generation from upstream-type TSFs in active mining operations. It focused on two areas in TSFs: the tailings beach and slope/dike surfaces. Two types of polymers—polyethylene glycol and poloxamer—were selected, and their effectiveness was evaluated in a series of phased laboratory and field tests. The lab tests investigated the moisture-retention capacity of the tailings after treatment with the polymer solutions as well as the ability of these solutions to reduce dust emissions. Polymers were applied to a tailings bed surface in the lab and dust was generated from this surface using a wind tunnel. PM10 and PM2.5 concentrations were measured using laser-diffraction dust sensors, and the polymers were found to have reduced dust emissions up to 95%. Small-scale wind-blowing tests were conducted in the field (specifically, in a controlled environment at a TSF) to evaluate polymer effectiveness on the tailings beach and slope/dike areas. The tests revealed that the AP could efficiently suppress approximately 80% of PM10 and PM2.5 dust emissions at both types of areas. Finally, 1000 gallons of AP solution were discharged at the top of tailings beach and slope/dike areas, respectively, and found to be effective. The results of these tests showed the high potential of the biocompatible polymers to be a feasible solution for reducing the respirable dust emissions from upstream TSFs in arid and semi-arid regions.

By Y. Wang, G. Xu, N. A. Amoah, A. Kumar

Mining-induced coal dust causes various respiratory diseases to mine workers, such as coal workers’ pneumoconiosis (CWP). Current available underground monitors are expensive, heavy and only measure mass concentration. These disadvantages limit them for regulatory sample monitoring purposes only while personal exposure levels for most miners remain unknown, risking miners to potential overexposures. Low-cost light scattering PM sensors offer a potential solution to this problem with capability of high spatio-temporal resolution PM characterization. However, these sensors require careful calibration before they can be applied in mining environments. There is basically no comprehensive study in the literature using a standard protocol assessing these sensors for coal dust monitoring. With the aim of calibrating the PMS5003 sensors for coal dust monitoring, we design the calibration method and system to calibrate these low-cost PM sensors coal dust monitoring. Working principles of present coal dust monitor and low-cost sensors are presented in detail. The linear regression calibration model which is used for the sensor calibration is further described. Sensor calibration and evaluation protocols are comprehensively compared and discussed. This investigation reveals the feasibility of low-cost sensors for real-time personal coal dust monitoring in underground coal mines.

Mar 2, 2022

By J. Cooper, M. W. Staub

Environmental management systems (EMSs) have been in use for more than a decade. US mining companies are only just beginning to adopt EMSs. This lag is primarily due to lack of market forces and lack of evidence that EMSs add value over standard compliance programs. Several recent studies concluded EMSs improve environmental performance and reduce costs. State and federal regulatory agencies are using EMSs as an innovative tool to streamline the regulatory process and achieve continual environmental improvements. The climate is right for the mining industry to adopt an EMS model that improves environmental performance and takes advantage of new regulatory programs.

Jan 1, 2004

By Leslie G. McMillion

A field project to develop and demonstrate a method for alleviating problems of highly-mineralized ground water where they occur as isolated zones or pockets in fresh-water aquifers is being conducted in the Ogallala Aquifer of eastern New Mexico by the Robert S. Kerr Water Research Center. Removal of contaminated water is by a large-capacity well and the pumped poor-quality water is used locally for secondary recovery of oil, Benefits of the operation are threefold in that the aquifer is being reclaimed for future fresh water production, contaminated water is being used beneficially, and fresh water which otherwise would have been used for waterflooding is available for other purposes. Ground-water quality in the site has improved markedly after 21 months of operation. Water quality in 15 specially-drilled monitoring wells has returned to the original quality level of the aquifer, and chloride concen¬trations in the pumping well have dropped to half the maximum level recorded thus far. Project results are very favorable and provide guidelines for initiation of similar undertakings in localities where needed.

Jan 1, 1970

By C. Restarick, R. G. Robins, R. M. Taylor, I. Ennis

Lime addition to acid mine drainage waters (AMD), possibly accompanied by aeration, has been the basis for their remediation by precipitation of predominantly metal hydroxides. An efficient novel alternative technique causes precipitation of double M(II)-M(III) hydroxy sulfates which readily precipitate and are easily dewatered. When the Fe(II)/Fe(III) + Al(III) ratio of the AMD is appropriate, the Green Precipitate (GP) Process provides a more effective alternative to normal liming/aeration. The process can be adapted to give a continuous in-line treatment by the choice of suitable computer-controlled reactors designed to improve the liming efficiency, reduce scaling and control the rate of treatment. The processes are described in terms of the chemistry involved.

Jan 1, 2000

By Roy M. Fleming, Christine B. New

The federal standard for limiting exposures to miners from radon daughters was reduced from 12 working level months (WLM) per year to 4 WLM per year in 1971. However, even at that time some researchers were concerned that the new limit would eventually be shown to result in an excess risk for lung cancer mortality in miners. The National Institute for Occupational Safety and Health (NIOSH) is now engaged in a comprehensive review of this topic. As the lead agency in this project, NIOSH has developed a work plan and established a work group to implement this plan. The procedure and specific considerations are outlined in the work plan for developing a comprehensive ionizing radiation standard recommendation for all miners, underground and surface. Such a recommendation will not only include estimates of health risks at various levels of exposure, but also appropriate recommendations for medical monitoring, sampling and analytical methods, sampling strategies, posting, engineering controls, personal protective equipment and recordkeeping. The work group has twenty-four members. Eleven members are NIOSH personnel representing six divisions of the Institute. The remaining thirteen members represent other federal agencies, specifically the Bureau of Mines of the Department of the Interior, the Mine Safety and Health Administration and the Occupational Safety and Health Administration of the Department of Labor, the Office of Radiation Protection of the Environmental Protection Agency, and the Bureau of Radiological Health of the Food and Drug Administration, Department of Health and Human Services. Several factors contributed to the decision to initiate this project. First, the efficacy of the current standard was considered. An initial study group was formed in the spring of 1980 by NIOSH to identify and evaluate articles that contained information on lung cancer mortality risks at and below the present permissible exposure limit. The conclusion drawn from their evaluation was that a two-fold excess risk of lung cancer mortality at and below 120 cumulative working level months (CWLM) of exposure to radon daughters is evident. This composite indication from selected studies was of sufficient magnitude to justify further evaluation. The study group, however, recognized that other studies and information must also be considered in a quantitative risk assessment which would form the basis for recommending an acceptable and feasible permissible exposure limit. A second factor in the decision to pursue further evaluation was the gaps in the current standard that had previously been identified by the Mine Safety and Health Administration (MSHA). These included lack of medical monitoring of underground miners and absence of regulations for surface miners. The seriousness of the health hazard relative to other hazards in mining was also considered. Along with exposures to silica and asbestos fibers, radiation was judged to be one of the major health hazards in mining, These combined factors constituted the justification to develop criteria and recommendations for improved mandatory health standards. The development process begins with a survey and review of the available world-wide information on the topic, including data and information developed by NIOSH. The end product of this review is to be a document that will contain an evaluation of the collected information and support for any recommendations that are made. To develop this document, the present work group has been divided into five task groups with the following emphases: Health Effects, Medical Aspects, Monitoring, Environmental Exposures, and Engineering Controls and Work Practices. The Health Effects task group is to evaluate the evidence from epidemiologic and animal studies of adverse health effects associated with all forms of ionizing radiation encountered in mining and milling operations. The "weight-of-evidence" of the results of all relevant and useful studies will be summarized, with the reasons for emphasizing the cited studies. The critical cells or tissues and the factors that should be considered in estimating the dose to these areas from various types of radiation will be identified. An evaluation will be made of the possible impacts of smoking and exposure to diesel exhaust on the determination of health effects related to radiation. The implications of biologically redundant dose in terms of the time between tumor initiation and death will also be analyzed. The Medical Aspects task group is to review the generally-accepted and the state-of-the-art medical technology for the detection of adverse health effects from ionizing radiation exposure. An evaluation will be made of the accuracy of urine and fecal analysis, wholebody counting, chromosome analysis and nose blows, as well as their usefulness for early detection of adverse health effects. Early detection is of little utility to the affected individual unless subsequent medical care can improve the prognosis. Recommendations for screening tests will be made after carefully considering the accuracy of the diagnostic procedures and the usefulness of early detection. Required recordkeeping and transfer rights will also be addressed. The Monitoring task group is to consider the state-of-the-art technology for the monitoring of occupational radiation exposures. Instrumentation, sampling strategies and analytical procedures will be reviewed for both personal and area sampling. The implications of the associated levels of confidence for non-compliance decisions will be evaluated. The discussion will also include an evaluation of the feasibility of replacing present monitoring systems with recent technology and the impact that a possible lower permissible exposure limit would have on monitoring requirements. The Environmental Exposure task group is to investigate the field procedures and mathematical methodologies which have been used to quantitate exposure levels to the various kinds of ionizing radiation. The magnitude and direction of the possible biases in past exposure assessments will be estimated. Specific attention will be given to the controversies concerning the quantification of the biological dose equivalent and the feasibility of recommending standards for mixed radiation exposures which use "rem" as the unit of measurement. The Engineering Controls and Work Practices task group will analyze the advantages and limitations of

Jan 1, 1981

By S. J. Cohen

Changes in our energy, national security, and commerce needs have necessitated identification of new sources of minerals, such as rare earths, lithium, copper, silver, aluminum, titanium, and the minerals on the U.S. Geological Survey’s (USGS) list of critical minerals (USGS, 2022). With the need to domestically produce these minerals, more mining will be required within the U.S. Some of these critical minerals deposit with naturally occurring radioactive materials (NORM), therefore, mining these minerals may concentrate NORM to the point that some states may require licensing and radiation protection programs. NORM is not regulated by the Federal government; it is regulated by the individual states. Consequently, overall national state of NORM regulation is chaotic with each individual state either choosing to regulate or not regulate NORM, and, if a state chooses to regulate NORM, then that state develops its own unique regulations. Further complicating the regulatory environment, states utilize a wide variety of strategies for regulating NORM, which sometimes results in inappropriate regulations, inconsistencies with specific radionuclides that are regulated, and inconsistencies with specific NORM types that are regulated. This paper will review the nature of NORM regulations, identify regulatory traps, and provide general guidance for identifying NORM and potentially avoiding regulatory jeopardy. Because of the chaotic nature of NORM regulations nationally, seeking guidance from qualified professionals with relevant expertise is recommended. Also, contacting the appropriate regulatory agency to gain a complete understanding of the NORM regulatory environment is useful for maintaining compliance.

Feb 1, 2023

By M. Misra

It is estimated that the volume of low -level and intermediate level contaminants present in the soil at different DOE sites is of the order of several million cubic feet. The existing remediation scheme is containerization followed by burial in Land Disposal Facilities (LDF's) which is economically unattractive warranting the need to develop alternate remediation routes. One such route is the physical separation based volume reduction approach to removing a MINIMUM AMOUNT OF CLEAN SOIL with the radioactive particles, reducing the amount of material that requires disposal. The purpose of this study was to evaluate and test the feasibility of using physical beneficiation techniques for removal of contaminants from soil. The performance criterion was to recover at least 80% of the activity in 20% or less of the original contaminated soil volume. Four different radioactively contaminated (primarily uranium and plutonium) soils from DoE sites namely LANL, INEL, Fernald Plant 1 Storage Pad (ID-B) and Mound soils were tested using gravity, magnetic, gravo-magnetic, hydrocyclonic and flotation devices. The paper is divided into the two sections. The first section presents the overview of the Heavy Metals in Contaminated Soil Treatability Project conducted at the University of Nevada, Reno (UNR) describing the salient features of a state-of-the art Soil Washing Laboratory and the technology equipments used in the test program. The second section describes the soil characterization and typical volume reduction results obtained from the UNR tests. Among the physical separation processes, only flotation processes passed the performance criterion. For the LANL and INEL soils where the contamination was contained in coarse particle size, it was possible to recover more than 80% of the activity in less than 10-20% of the original volume of the soil thus rendering 80-90% of the soil "clean". For Fernald and Mound soils where contamination was of colloidal nature, flotation based processes showed encouraging results and are recommended for further studies.

Jan 1, 1995

By Robert J. Wright

The purpose of this paper is to propose a classification of uranium deposits that is believed to be well suited to the needs of uranium exploration and resource assessment. By way of background some observations are offered about mineral exploration in general, and uranium in particular. Attention is first given to the we of models in mineral exploration. Some general principles of mineral deposit classification, the basis for model formulation, are then considered. Finally, the uranium classification is presented.

Jan 1, 1979

By LeRoy D. Loy

The coal mining industry must be able to compete with alternate sources of fuel for the utility and industrial customers. If the industry is unable to control transportation costs, either due to government interference, or for other reasons, then mining costs must be kept down. Australia, South Africa, Canada, (and later Colombia) will take larger shares of the export market if mining costs are not kept competitive. The government's environmental regulations must be met without incremental increases in mining costs. Entrepreneurial instincts must be retained by the industry to provide for their investment in the future. What are the Problems with Existing Research? Government funding for coal mining research has been reduced or virtually eliminated. BCR (Bituminous Coal Research) is now a membership- supported organization, but its primary focus has been on health and safety-oriented research. BCR, however, is now attempting to widen its scope and conduct other types of research. There are almost no funds in EPRI's (Electric Power Research Institute) program for coal mining research. Large mining companies do some research for their own purposes and needs, but this is proprietary and therefore results are not shared with the remainder of the industry. The mining industry as a unit is not undertaking productivity (systems) oriented research in any common or cohesive manner.

Jan 1, 1983

By Chaitanya "Teny" Mittal

INTRODUCTION A team effort by the Owner, Engineer, and Contractor can help avoid serious problems on a construction project. It can save cost and time for both Owner and Contractor, as illustrated in the following case history of the West Zone and Siouf Keblia Collector System in Alexandria, Egypt (Contract 02-AID-83/84). Under the bilateral agreement made in 1980 between the United States of America and the Arab Republic of Egypt, the United States, through the Agency of International Development (USAID), gives approximately $1 billion per year as a grant to Egypt for various development projects. The Alexandria Wastewater Management System was selected in 1981 as one such project. The Egyptian Government Agency responsible for this work is the Alexandria General Organization for Sanitary Drainage (AGOSD). A joint venture of two U.S. consulting engineering firms, CH2M HILL, Inc., and Metcalf & Eddy, Inc., called Wastewater Consultants Group, along with two local subconsultants, Engineering Consulting Group and Warith Engineering Co., were selected by AGOSD to study the sewer system and develop a plan to serve the immediate and long-range sewage disposal needs of Alexandria. Wastewater Consultants Group is currently involved in Phase I of the Master Plan. This initial step in providing Alexandria with an operating sewerage system for the current and near-term population (year 2000) consists of the design and construction management of 140 kilometers of collector and force main pipelines (including 9 miles of pipe jacking and tunneling in very soft clay), five new pumping stations, extensive rehabilitation of two treatment plants (built in the 1960s but never operated successfully), and installation of a sludge handling system. Phase I is scheduled to be completed by the end of 1991 at a total cost of around $250 million (US) plus 250 million

Jan 1, 1989

By V. A. Shea-Albin

Sandstone escarpments surrounding western coal-bearing plateaus serve as critical habitat for animal species. Effects of mining subsidence on escarpment stability are not well documented; therefore, regulatory agencies may limit extraction of coal reserves underlying escarpments. Because millions of tons of this coal exist on Federal Lands, associated public revenues from Federal royalties, and valuable coal reserves, risk being lost. The U. S. Bureau of Mines is using numerical modeling techniques to analyze effects of subsidence on escarpment stability. Finite element models that incorporate bedding plane slip, gob formation, and movement along joints simulate escarpment subsidence observed in the field.

Jan 1, 1994

By N. A. Frazier

The goal of the U.S. nuclear waste management program is to provide assurance that existing and future nuclear waste from military and civilian activities, including spent fuel from the once-through nuclear power cycle, can be isolated from the biosphere so as to pose no significant threat to public health and safety. The U.S. Department of Energy (DOE) is responsible for defining and implementing this national waste management effort. The Environ- mental Protection Agency (EPA) and the Nuclear Regulatory Commission (NRC) are responsible for providing a framework of criteria, standards, and regulations that will assure that the disposal methods developed by DOE are consistent with the achievement of the goal of safe, long-term waste isolation. Within DOE, the responsibility for implementation of the national waste management program rests with the Office of Nuclear Waste Management. The nuclear waste management effort involves three major activities: The Defense Waste Management Program, the Spent Fuel Storage Program and the Commercial Waste Management Program. The major programmatic effort in the Commercial Waste Management Program is the National Waste Terminal Storage (NWTS) Program.

Jan 1, 1981

By Saurabh Kundu, Shakuntala Tudu, Indrajit Paul, Chandra Sekhar, Manikanta Nallamilli, Shaik Mahaboob Basha, Neha Gupta, Srinivas Dwarapudi, Dhiraj Madhukar Kadhe

Iron ore pelletizing using compressive and shear action on wet mixture feed has been studied. The physical properties, namely, moisture content, drop strength, green compressive strength (GCS), dry compressive strength (DCS), porosity, and cold crushing strength (CCS), have been studied. Pelletizing tests were carried out on four different types of ore, namely, hematite ore, magnetite ore, goethite ore, and sinter return fines. The inference of shear forces on silica distribution index in dry pellet has been studied using optical and scanning electron microscopy. Significant improvement in physical strength was observed due to compressive and shear forces on the pellet mixture feed. However, decrease in moisture content and ball porosity has been observed. Silica distribution index improved by 1.72 times for hematite ore, 1.47 times for magnetite ore, and 1.68 times for goethite ore. It has been found that bubble cavity has been reduced which is good indicator in terms of physical properties.

Jan 29, 2022