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By Anthony D. Szpak

The purpose of this program was to demonstrate the feasibility of Illuminating various types of underground coal mining machinery as required by the Federal Coal Mine Illumination Standards Part 75.1719 to 75.1719-4 Code of Federal Regulations Title 30. Nine various machines were illuminated and the illumination systems were evaluated for a 3 month period of operation. Factors evaluated were ease of implementation, reliability, ease of maintenance, acceptance by mine workers and operators, Illumination degradation and durability.

Jan 1, 1981

By W. L. Swager

Tramp (undesirable) elements introduced into iron and steel castings via purchased ferrous scrap are evaluated as to their likely degree of future threat to the quality of castings. Conclusions are based on analysis of literature and on nonmail surveys of foundries, scrap processors, trade and technical associations, and others. The existing tramp-element problem is expected to be persistent, but amenable to improved control by foundries and their suppliers. Four recommendations for action are given.

Jan 1, 1981

By Burton J. Thamer

Radon emanation coefficients of 0.02 to 0.55 were measured at moisture contents ranging from dry to saturation in eighteen different ores. The emanation coefficients rose from a minimum when dry to a plateau usually starting at 5-20 percent of saturation. A model, using measured pore-size distributions, suggested that the radium mineralization may be confined to annular layers about 0.02 micrometers thick around pores. Radon's diffusion coefficient was determined as a function of moisture. The techniques involved comparing a disc's exhalation as a function of time whether or not the disc had a distributed source. The model was free of approximations and included the effects of porosity and adsorption. An increase of diffusion coefficient with moisture for one or two ores was explained in terms of a model's equation for the diffusion coefficient in terms of both volume and surface diffusion. Radon's adsorption coefficient was determined on a uranium ore.

Jan 1, 1981

By Michael A. Staiano

The objective of this study was to determine the magnitude and sources of environmental noise from mining operations near populated areas, to de-scribe monitoring techniques, and to identify applicable existing noise abatement techniques. To this end, noise surveys of a representative sample of mines and quarries were conducted. Noise levels at site boundaries and near specific equipment and ensembles of equipment were measured. Noise exposures in terms of annual day-night sound level were calculated for the boundary noise measurement locations. In addition, the relative sound level contributions were estimated for the mining equipment noise sources affecting the boundary locations. Noise abatement methods falling into three categories were analyzed: equipment practices, operational/administrative practices, and equipment quieting. Selected applications of noise abatement methods were evaluated in hypothetical situations with emphasis upon machinery selection and use. Procedures for measuring noise around mining operations were provided.

Jan 1, 1981

With increasing depth of mining, geotech nical factors assume increasing importance in the design and operation of open pit coal mines. Dragline strip mines are particularly sensitive to stability conditions since the draoline is a relatively inflexible machine, particularly in relation to its limited dump- ing radius for overburden disposal. Geotechnical factors relevant to strip mine design include: 1. spoil pile stability 2. wall stability 3. floor stability 4. excavation characteristics 5. groundwater conditions A basic geotechnical investigation pro- gram for new mine feasibility studies is described. This includes: 1. terrain evaluation 2. geotechnical drilling and logging 3. geophysical logging 4. materials testing 5. seismic refraction traversing 6. groundwater studies Such a program will give an overall geotech- nical assessment of the site and highlight any areas which may require further, more detailed Investigations

Jan 1, 1981

By Daniel Threlfall

The disposal of hazardous chemical wastes will be one of the major environmental issues of the 1980's. Approximately 50 million tons of hazardous wastes are produced yearly. One of the major aspects of the problem is the siting, design and construction of environmentally acceptable disposal facilities to accommodate this huge volume of material. Surface mines have been considered attractive for development as disposal sires for several reasons: 1. Surface mines represent an open pit that can conveniently serve as a repository for wastes. This could represent a significant economic savings when compared with sites on undisturbed lands chat might require extensive excavation or embankment construction.

Jan 1, 1981

This Bureau of Mines publication consists of an overview of the mine waste management research currently being conducted by the Bureau. The following papers, given at a Technology Transfer Workshop, emphasize the increasing importance of research related to the safety and environmental considerations of mine waste disposal In recent years. Current work related to legislation passed in the last 10 years and their subsequent standards includes the development of adequate monitoring systems, development of stability and seepage prediction and control techniques, control of runoff water, and control of leaching solutions. Selected topics are included here that cover coal mine waste disposal, embankment slope stability monitoring, flow failures of mine tailings impoundments, and controlled burnout of abandoned coal mine fires. The projects described provide a current documentation of problems being addressed.

Jan 1, 1981

By King K. Mak

The objectives of this study are to: (1) Assess current signing regulations and practices; (2) Develop effective signing guidelines; and (3) Evaluate the applicability and appropriateness of the proposed signing guidelines through field demonstration at representative mines. A literature search was conducted to determine the state of the art for signing applicable to surface mine haulage roads as well as survey of existing MHSA regulations and review of MSHA accident records. Nine representative mines were visited to gather information on current signing practices. Preliminary signing guidelines were then developed based on the abovementioned data. Field demonstration of the preliminary signing guidelines was conducted in which signing programs were implemented in two selected mines. Signing requirements were first assessed at each of the two participating mines. Subsequently, the necessary signs were designed, purchased, and installed at the two mines. Evaluation of the signing program as to its adequacy, appropriateness, and effectiveness was solicited from both mine management and operations personnel. Experiences gained from field evaluation were then incorporated into the final signing guidelines as presented in this final report.

Jan 1, 1981

By Rudolf E. Greuer

This report contains the practical application of a computer program for the simulation of ventilation systems under the influence of mine fires and other emergencies on five hardrock mines. The introduction describes the need for such a program, its basic features, and the range of its applicability which is mainly a function of the available ventilation data. The second chapter discusses program modifications, whose necessity or desirability was, during the application, discovered. The following five chapters, which comprise the major portion of the report, give the detailed description of the program application on the five mines. For every one of the selected mines, the ventilation system, the source of the used ventilation data and their preparation for computer simulations are outlined. Based on data for the airflow distribution solely, fumes concentrations in the mines are calculated for several assumed fire locations. Based on data for airflow and pressure distributions, ventilation disturbances caused by fires as well as the resulting fumes concentrations and temperatures are determined. The consequences for escape routes and the possible means to keep them free of fumes are discussed. To investigate the capabilities of the program, other contaminant sources and other potentially dangerous ventilation factors, like fan failures and changed surface temperatures, are simulated also. The results of the calculations have been entered into ventilation plans which makes them easier to scrutinize. All significant computer printouts have been attached.

Jan 1, 1981

By C. E. Roessler

Uranium and its decay series are associated with phosphate deposits of marine origin. Uranium concentrations are on the order of 100 to 200 ppm in matrix from the Bone Valley formation of Central Florida and about 25% this value in matrix mined from the Hawthorne formation in North Florida. Occupational radiation exposure due to this source has been under study in Florida since the mid 1970's (Windham, Partridge, Horton 1976; Roessler and Prince 1978). This report is based on findings of an industry-wide scoping survey conducted by the University of Florida during March 1976 through May 1977 and subsequent studies in selected individual facilities. PHOSPHATE MINING OPERATIONS Mining and beneficiation operations are diagramed in Figure 1. At the excavation site, electric powered draglines remove the overburden and expose the phosphate matrix (ore) which is then slurried and pumped to the beneficiation site. At the washer stage of the beneficiation plant, the matrix is subjected to washing and screening. A coarse product, "pebble" is produced and sent to storage piles while the fine fraction is passed through a series of cyclones to remove the clays. The generated clay suspension is sent to settling ponds while the remaining sand-sized fraction is sent to the flotation plant. At the flotation plant, phosphate particles are recovered from the fine sand particles of similar size through several stages of treatment with reagents, agitation and separation of floating and sinking fractions. The high grade concentrate produced is transferred to storage while the sand tailings are discarded. [ ]

Jan 1, 1981

By Stanley Ferguson

Since 1978, the Colorado Department of Health has become involved in specific investigations of possible radiation hazards among nonminers in Colorado communities. In each instance, the improper disposal of mill tailings has precipitated concerns and allegations of radiation hazards. This presentation is a brief summary of the findings, to date, of 4 such investigations involving tailings disposal problems in Canon City, Denver, Durango and Grand Junction, Colorado. Canon City In the summer of 1979, allegations of excessive cancer incidence were made at public hearings concerning an application for a Radioactive Materials License submitted to the Colorado Department of Health by the Cotter Corporation for a uranium mill at Canon City. Canon City is the site of a uranium mill operated since 1958 by Commonwealth Edison. Local residents accumulated figures and calculated rates suggesting a 2-fold excess in total cancer mortality. These rates were not adjusted or standardized for demographic varibles. A review of cancer mortality data and computation of age standardized rates for years 1950 through 1977 showed that Canon City's cancer mortality rates were within expected limits, actually lower than rates for the State of Colorado or the United States. The first slide shows rates for every fifth year, 1950 through 1975. Further, an analysis of Canon City cancer incidence data from the Colorado Central Cancer Registry revealed that 1979 incidence rates were not significantly different from Colorado rates, with the exception of prostate cancer. The next slide shows age standardized incidence rates for lung, colon, breast and prostate cancer. Data were also reviewed for leukemia, myeloma, lymphoma and cancers of the thyroid stomach, uterine certix, ovary, kidney, bladder-and brain, however, small numbers of cases prevented meaningful rate calculation. 1980 data are presently being analyzed. None of the data yet examined support allegations of radiation-associated cancer in Canon City. Denver In February of 1979, the Department of Health became aware of a number of radium mill tailing deposits in the Denver metropolitan area, remnants of the radium milling industry of the early 1900's. Several of the deposits were situated so as to possibly contribute significantly to radiation exposure of a small number of people over a period of several decades. The Department developed protocols for radiation surveys, dosage estimates and, for a small number of persons, body burdens determinations and peripheral blood lymphocyte cytogenetic studies. The results of this investigation suggested no measurable biomedical impact as a result of the radium deposits. Durango In October of 1979, a physician residing in Durango, Colorado released information from a preliminary analysis of lung cancer data suggesting an incidence rate several times expected in that city. The data were presented at a meeting of a citizen's group concerned about the possible health hazards of 2 uranium mill tailing deposits located in the south end of the city. Since cancer incidence data generally do not exist in most of western Colorado, a team of epidemiologists was dispatched to Durango to work with local physicians and hospitals in conducting an epidemiologic study of selected cancers for the period 1969 through 1978. After case-finding and record abstracting were completed, it was determined that sufficient data were available for study of only 3 sites: lung cancer, breast cancer and leukemia. The next slide shows age standardized incidence rates for these 3 sites for 1969-1978 for Durango and the State of Colorado. There are no significant differences in these rates. The data did show a geographic peculiarity with regards to the relative proportion of tumor types near the tailings deposits as opposed to away from the deposits, however, this finding is based upon very small numbers of cases and may represent only the random excursion of rates based upon small observations. This investigation suggests that if a carcinogenic hazard is present, it is too small to be detected by the study method employed. Grand Junction The Department of Health has been involved in the Grand Junction mill tailings problem for several years. In 1966, the Department issued an order terminating the practice of free public access to a 55-acre pile of uranium mill tailings. Prior to this order, an estimated 300,000 tons of material was removed. Of this amount, an estimated 50,000 tons was presumably used in residential and commercial construction. Despite many allegations of cancer and birth defects excesses in Grant Junction since the mid 1960s, the first epidemiologic study of cancer was conducted in the spring of 1977. Data from the Colorado Central Cancer Registry were analyzed and reported to the Executive Director of the Department of Health in June of that year. The findings of the first and preliminary study were an unexplained excess of acute leukemia and chronic myelocytic leukemia. The excess was based upon small numbers but was present across all age groups. No increase in chronic lymphocytic leukemia was evident.

Jan 1, 1981

By M. P. Saunders

A comprehensive, site specific water management plan is of primary importance to the successful implementation, operation and decommissioning of any mining project. Formulation of a plan requires an orderly planning process consisting of identifying problems, establishing planning criteria based on the guidelines and requirements of regulatory agencies, and an iterative procedure of identifying, investigating, and evaluating plan elements and alternative plans. A typical uranium surface mine operation consists of a mine pit or pits, spoil pile areas, crusher, processing plant, and tailings disposal area. A water control plan addresses the problems of diversion of natural runoff from undisturbed areas around the mine; and diversion, collection, and treatment of runoff from within the mine area. A water control plan is required to determine the location and size of appropriate control and detention structures; their cost; and the schedule for permit activity, design, and construction. The plan must be formulated to meet the requirements of both the State and Federal regulatory agencies.

Jan 1, 1981

By W. W. Aljoe

The use of protective canopies can result in canopy roofing and/or serious restrictions to operator comfort and vision. To document this experience, BCR conducted a field study of cab and canopy design and application which resulted in a catalog of 164 canopy designs and an analysis of field data which showed no simple relationship between working height and canopy-related problems. The relationship also involves (1) machine frame height, (2) mine floor undulations, (3) operator compartment dimensions, (4) canopy design and location on the machine. Data analysis indicates (1) present technology does not always permit successful application of canopies in working heights below 42 inches, and (2) development of satisfactory low-coal canopies is doubtful. The basic conclusion of the study is that future R&D studies should be directed at development of alternative protection systems and remote mining methods.

Jan 1, 1981

By David C. Mulder

As a result of the dramatic growth of Edmonton, Alberta during the past decade and the rapidly increasing price of natural gas, Edmonton Power has received provincial government approval to construct and operate an 8O0-megawatt- capacity coal-fired thermal generating station at Genesee, about 50 km southwest of Edmonton. The power plant will consist of two 400-megawatt steam-driven thermal generators, with provision in the future for two or more additional units. The coal will be hauled by truck from the nearby three-million-tonnes- per-year strip mine, with economically recoverable reserves exceeding two hundred million tonnes. Edmonton Power controls a major part of the coal leases in the area, and is working with other lease holders in developing the most efficient mining plan. A natural depression was selected as the site for the 600-hectare cooling pond to provide water for the power plant. Edmonton Power is working closely with the people in the area to ensure that their rights and concerns are communicated and recognized by all parties.

Jan 1, 1981

By L. B. Phelps

A method is presented for the burial of potentially toxic spoil in high density zones or packages within spoil piles. Such burial could reduce the outflow of pollutants and thus minimize contamination of groundwater flows. Laboratory model studies using ammonium bromide tracer were performed to quantify the expected outflow mixing that could be achieved through package construction in spoils. Field drilling and geophysical density logging of spoils was carried out at three sites in Pennsylvania and Ohio to obtain a range of field spoil bulk density measurements and spoil samples. These data are analyzed to determine the relationships between spoil density and the controlling factors of lithology, depth, age, particle size distribution and mining method. A separate series of spoil permeability tests were performed in the laboratory to investigate the relationship between permeability and its related parameters. Research results are applied to the toxic package method to suggest guidelines for pack-age size, shape, density and placement for future field prototype development.

Jan 1, 1981

By Martin Smirlock

A novel instrumentation system has been developed which enables simple, quick, and accurate measurement of vehicular dynamics within low speed ranges. The system, consisting of a microwave transceiver and microprocessor data acquisition and reduction system, measures the deceleration dynamics of low-speed mining and construction equipment. It makes the basic measurement, calculates key parameters such as average deceleration, initial velocity, stopping distance, and brake system delay time, and produces autoscaled graphs of velocity, acceleration, and displacement versus time.

Jan 1, 1981

By F. S. Kendorski

This report presents the results of a program to improve, using existing and proven technology, unstable highwall conditions through better blasting practices in Appalachian strip coal mines. Better borehole blasting agent distribution and optimization of burden, spacing, and delay periods allowing satisfactory breakage with minimal backbreak were the objectives. At a selected field site, geologic conditions were closely examined with regard to joint orientation and spacing, and resulting slope stability considerations. A test series of eight blasts was completed and the resultant highwall monitored by repetitive photography. The study of drilling and blasting economics along with equipment performance led to an economic model of blast parameters and the identification of blast design cost benefits. The work demonstrated that small strip mining companies' are able to achieve a more stable highwall excavation utilizing presently available technology, equipment, and explosive products at improved operational cost and safety.

Jan 1, 1981

By Gary L. Stecklein

This final report delineates the findings of the test programs, simulations, and analyses performed to determine the requirements for the effective application of berms and guardrails as truck restraint systems for elevated mine roadways. Included arts criterion for effective vehicle restraint for guardrail applications and recommendations for berm applications based on scale model tests and computer simulations. Full scale haulage vehicle-berm interaction field tests were performed to correlate the results of these model tests and computer simulations. Recommendations for the construction of berms were made on the basis of tests of berm bearing strength, response of the vehicle to different berms, and predictions based on the obtained correlation

Jan 1, 1981

By N. S. Shan

This report presents the results of a study to determine compaction criteria for coal waste embankments. The purpose of this study is to evaluate the costs and resulting effects on the engineering proper-ties of coal waste materials, utilizing different compaction methods, equipment passes, and lift thickness. Based on the results of the study, a cost efficient compaction method that will attain the desired results will be recommended to the coal mining industry. The report describes a comprehensive literature search into the compaction of coal waste materials, field compaction programs, laboratory investigations, analysis of test data as well as conclusions and recommendations for establishing the compaction criteria. The findings obtained in this investigation are intended to supply much needed information and to justify the guidelines that have been recommended.

Jan 1, 1981

By M. M. Ayoub

With a return to coal as a major energy source for many companies, more emphasis is being placed on recovery of coal from areas that were formally considered uneconomical to mine. Increasing emphasis is being placed on production from low coal (seam height 48 inches or less) as high coal seams are depleated. Mining in restrictive spaces requires unusual work postures that can turn easy jobs into demanding ones. The objectives of this research were: (1) to evaluate the job demands associated with low coal mining, (2) to survey the anthropometry, strength, and aerobic capacity of low coal miners to determine if they differ from the U. S. population, and (3) to recommend, on the basis of available information, optimal job and work station design for low coal mining. This research effort was supported by the U. S. Bureau of Mines. The male and female anthropometry with the exception of weight and circumferential dimension, was quite similar to the comparison population. Back strength for male and female miners was significantly lower than the industrial worker population. This can be one of the contributing factors of low back problems in mining. Shoveling, timbering, and helpers tasks were physiologically demanding activities. However, due to the frequent stoppage of work, adequate rest was usually available. If work stoppage is corrected, then better work/rest schedules are essential.

Jan 1, 1981