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By Jr. Watts, B. K. Cantrell, D. H. Carlson, K. L. Rubow

"Abstract — The use of diesel equipment in underground coal mines is controversial because the National Institute for Occupational Safety and Health (NIOSH ) regards ""wholediesel exhaust"" as ""a potential occupational carcinogen."" Threshold limit values (TLVs ) are recommended for the gaseous pollutants CO, CO2, NO, NO2, SO2 and some hydrocarbons emitted in diesel exhaust. There is, however, no TLV recommended for diesel exhaust aerosols (DEA) nor is there a standard method for sample these aerosols.The University of Minnesota and the USBM have collaborated to develop a personal diesel exhaust aerosol sampler (PDEAS) that utilizes size selective, partial impaction and gravimetric analysis. During the field tests of this sampler, numerous air quality measurements were conducted in underground coal mines that used diesel equipment. The objective of this report is to present these data and to assess the impact of diesel face haulage equipment on mine a quality.Air quality data were collected in four underground coal mines. The mines used continuous miners and diesel haulage equipment. Daily samples were collected at the section intake, haulage way and on haulage vehicles. Both full- and partial-shift samples were collected using a variety of aerosol instruments. These included the PDEAS and the micro-orifice uniform deposit impactor (MOUDI) that sample the mine aerosol diesel exhaust fraction. Two of the mines were also monitored for the major gaseous constituents found in diesel exhaust CO,CO2, NO, NC, and SO2. These measurements were made by either collecting bag samples for subsequent gas analysis or by Palmes dosimeters.Concentrations of CO, CO2, NO, NO2 and SO2 were well below regulated levels. The mine average DEA concentration determined by the PDEAS in the haulageway for the three mines surveyed was 0.79 mg/m4, with a standard deviation of 0.19 mg/m3 DEA contributed 65% of the respirable aerosol, at this location. These results were the same as the mean DEA concentrations calculated from size distribution measurements obtained using the MOUDI. This was 0.78 mg/m3, with a standard deviation of 022 mg/m3."

Mar 1, 1992

By B. W. Gandrud

This report, consisting mostly of float-and-sink data and washability curves, has been prepared in connection with an exhaustive study of coal preparation in Alabama conducted, by the U, S. Bureau of Mines and the University of Alabama with the cooperation of the different coal operators On the basis of the float-and-sink data, an attempt has been made to determine approximately the extent of ash and sulphur reduction obtainable under given conditions on coal from the mines which were sampled, In the coal-producing districts of Alabama a great deaf of attention has been given in recent years to the problem of improving preparation methods so as to obtain from various coal beds the best possible grade of washed coal. This is especially so where the washed coal is used for the making of metallurgical coke in by-product plants or where there are possibilities of using the coal for this purpose. In the manufacture of metallurgical coke, the sulphur content of the coal is a very important consideration. It is quite often the determining factor as to whether or not a certain coal can be used for coke making. In the studies which form the basis for this report, all samples have been analyzed for sulphur in order to obtain information regarding the possibilities of sulphur elimination as well as ash reduction, and the samples on which reports are made were obtained from beds that are characterized by rather high percentages of sulphur. In connection with the present investigations of coal preparation in Alabama a standardized method of interpreting float-and-sink data has been used extensively for predicting the ash and sulphur reduction and yields obtainable in a commercial washing plant from various sizes of raw coal and from the raw coal as a whole after a certain degree of crushing. This method, which will be explained in subsequent chapters, was used in interpreting the data contained in this report. The samples used for these washability studies were obtained from the following mines in the Warrior field of Alabama: Beltona mine on the Jefferson bed; Dolomite and Mulga mines on the Pratt bed; Coal Valley No. 163 and Coal Valley No. 11 mines on the Corona bed; Cedar Cove mine on the Carter bed.

Jan 1, 1932

By B. W. Candrud

This report, consisting mostly of float-and-sink data and washability curves, has been prepared in connection with an exhaustive study of coal preparation in Alabama conducted by the U. S. Bureau of Mines and the University of Alabama with the cooperation of the different coal operators on the basis of the float-and-sink data, an attempt has been made to deter-mine approximately the extent of ash and sulphur reduction obtainable under given conditions on coal from the mines which were sampled. In the coal-producing districts of Alabama a great deal of attention has been given in recent years to the problem of improving preparation methods so as to obtain from various coal beds the best possible grade of washed coal. This is especially so where the washed coal is used for the making of metallurgical coke in by-product plants or where there are possibilities of using the coal for this purpose. In the manufacture of metallurgical coke, the sulphur content of the coal is a very important consideration. It is quite often the determining factor as to whether or not a certain coal can be used for coke making. In the studies which form the basis for this report, all samples have been analyzed for sulphur in order to obtain information regarding the possibilities of sulphur elimination as well as ash reduction, and the samples on which reports are made were obtained from beds that are characterized by rather high percentages of sulphur. In connection with the present investigations of coal preparation in Alabama a standardized method of interpreting float-and-sink data has been used extensively for predicting the ash and sulphur reduction and yields obtainable in a commercial washing plant from various sizes of raw coal and from the raw coal as a whole after a certain degree of crushing. This method, which will be explained in subsequent chapters, was used in interpreting the data contained in this report. The samples used for these washability studies were obtained from the following mines in the Warrior field of Alabama: Beltona mine on the Jefferson bed; Dolomite and Mulga mines on the Pratt bed; Coal Valley No. 16B and Coal Valley No. 11 mines on the Corona bed; Cedar Cove mine on the Carter bed.

Jan 1, 1932

By James A. Wasson

This report summarizes the results and conclusions reached by various investigators who have attempted to determine the extent to which hydraulic fracturing will affect the secondary recovery of crude oil by waterflooding. It also discusses the most advantageous use of this well-stimulation method in waterflood projects. A thorough search of the literature was made, and pertinent information was abstracted from appropriate reports. A carefully designed and controlled program of formation fracturing is an effective aid in waterflooding because it increases water-injection and oil- production rates. Generally, fracturing has resulted in little or no reduction in ultimate oil recovery, but under certain circumstances recovery has been substantially increased.

Jan 1, 1963

By J. Adkins

This document presents a description of the results of a project aimed at producing a broad description of current mining training programs and an evaluation of their effectiveness with respect to reducing mine injuries. Aggregate training and injury data were used to evaluate the overall training effort at 300 mines as well as specific efforts in twelve categories of training course objectives. From such evaluations, recommendations were derived with particular emphasis being placed on identifying program characteristics that tend to be associated with effective training. Recommendations were also formulated with reference to role changes in industry and government interaction with respect to training programs, new or additional training programs, changes in the types of course materials and training methodologies, and recommendations concerning new areas for investigation.

Jan 1, 1976

By BUREAU OF MINES

In 1948 the United States became a net importer of oil. Coupled with an unpre- cedented domestic production of 5,900,000 barrels daily, imports approximating 500,000 barrels made available a total supply of 6,400,000 barrels a day. Thus, by herculean effort, the oil industry was able to meet an extraordinary demand at home and, in addition, to ship abroad almost 400,00 barrels daily of petroleum and products. The country's oil position now differs greatly from that prevailing at the be- ginning of World War II. Then, actual oil production averaged about 4 million bar- rels a day, and productive capacity probably was greater than 5 million barrels a day. As the demand of the military and industrial machine grew with the rising tempo of the drive toward victory, the United States not only met its own needs but pro- duced about two-thirds of the total oil requirements of the Allied Nations, excluding Russia. As a people, we can be deeply grateful that the Nation's petroleum resources were adequate and sufficiently developed to support such a tremendous effort. Even in those critical hours when immediate needs were the paramount issues, a prudent Congress paused to contemplate the importance of an assured long-term supply of liquid fuels. From these deliberations came the Synthetic Liquid Fuels Act of 1944, which authorized research and development work on new sources of oil coal, oil shale, and agricultural and forestry products. ce World War II, a civilian demand for 6 million barrels of petroleum prod- ucts has become the order of the day every day. By drilling as many as 39,000 new wells a year, the production rate has been increased enough to meet domestic require- ments by a bare margin. Some imports were necessary, however, to fill both domestic and foreign demands, and these doubtless will increase. Is this policy of exploration within the United States and the development of oil in foreign countries adequate insurance for the fulfillment of our future national needs? This question has two aspects one purely civilian and economic in character and the other significant from the standpoint of our national defense. There are now approximately 4,000 producing oil fields in this country. At first thought, it would appear that production could decline in a considerable number of these fields without materially affecting the over-all daily output. However, 48 percent of the oil comes from only 111 major fields which contain 50 percent of the total proved domestic reserves. It is apparent, then, that the flow from large fields - having proved reserves of 100 million barrels or more each must be sustained if daily production is to be kept at the present levels. Essentially, this means that new major fields must be discovered about as rapidly or perhaps more rapidly than the older ones lose productive capacity. From 1940 through 1947, only eight major fields with estimated reserves of more than 100 million barrels each, were discovered and proved - an average of one such field a year. The total estimated reserve of these eight fields was less than 1 year's supply at the present rate of use. As drilling continues, some existing fields ultimately will prove reserves larger than those now known. Without a pronounced increase in the num- ber of major discoveries, however, the prospects for increasing our present productive level are not encouraging. Any gap that appears between domestic productive capacity and demand could be filled with supplies from proved oil resources abroad. Assuming cheap pipe-line and tanker transportation to the United States, freedom from exorbitant taxes and charges

Jan 1, 1949

By Forrest T. Moyer

All general measures of the safety record of the coal mining industry worsened appreciably in 1970. Injury experience for the year was 260 fatal and 11,552 nonfatal injuries at respective frequency rates of 1.00 and 44.40 per million man-hours of worktime. The fatality total was 57 higher and the rate of occurrence was 18 percent higher than the corresponding figures of 203 fatal injuries with a frequency rate of 0.85 in 1969. The worsened fatality record in 1970 resulted primarily from a major disaster (a single accident which results in the death of five men or more) on December 30, 1970, that killed 38 men. There were no major disasters in 1969. The total of 11,552 nonfatal injuries in 1970 was the highest annual total since 1960. It was 1,635 higher and the frequency rate was 6 percent higher than the corresponding totals for 1969 of 9,917 nonfatal injuries occurring at a rate of 41.76. The injury severity rate of 8,308 days lost or charged per million man-hours was 13 percent worse than that of 7,359 in 1969. Similarly, the average severity of 183 days lost or charged per injury in 1970 was 10 days or 6 percent higher than in 1969. Aggregate worktime of 260.2 million man-hours and production of 609.8 million tons in 1970 were, respectively, 10 and 7 percent higher than in 1969. An average of 144,480 men were at work on an average of 227 active days in 6,316 mines and 544 mechanical cleaning plants during 1970.

Jan 1, 1973

By Robert M. Becker

This investigation (in five parts) extends the theory of sample reliability from a sample consisting of a fixed number of items to a sample consisting of a fixed amount of items. Examples of a fixed amount of items per sample are samples consisting of a fixed weight or a fixed volume of unequal size particles. The extension of the theory is confirmed by experimental laboratory sampling using standard procedures. The probability distribution functions (the binomial, hypergeometric, multinomial, generalized hypergeometric, and those here called the compound binomial and compound multimomial functions) are developed from fundamentals. Their distributions are generalized to include some measured characteristic of the items. Infinite population moments are derived from moment-generating functions, and finite population moments are developed from corresponding infinite population moments using a newly defined mathematical operation. The first three experimental moments in laboratory sampling to given weights of particles are compared with the theoretical moments of their corresponding compound mult.inomial distributions. The agreement is striking. The study is divided into five parts. Part 1 deals with probability or random sampling to n items and with all sampling to n items per sample from some one probability distribution. This is the area of sampling covered by well-known theory. Accordingly, the procedures may be different but many of the results are well known.

Dec 1, 1964

By Curt D. Jr. Edgerton

This study was made to determine trends in fresh water usage by California petroleum refineries, to Forecast fresh water requirements to 1975, and to evaluate water conservation practices. Statistical data used in the study were obtained largely from published sources and from records of selected companies. An adequate sampling of the State's refining capacity was obtained, and the data were extrapolated to the total California refining capacity. A breakdown of the data was then made on the basis of the following refining regions: (1) the Los Angeles Basin and Southern Coastal region, (2) the Southern San Joaquin Valley, and (3) the San Francisco Bay area. An unpublished forecast of crude oil input to refineries by a major oil company operating on the West Coast was used as a basis for predicting fresh-water usage. The 1963 fresh water intake by California petroleum refineries was 84 million gallons per day. This is expected to increase to 128 million gallons per day by 1975. The fresh-water to crude-oil ratio is increasing in all regions except the Southern San Joaquin Valley. At present, the supply of fresh water available to almost all of the State's petroleum refineries, mostly from surface sources and company-owned wells, is adequate, although shortages may develop within the foreseeable future. Present conservation methods are centered around the following four objectives: (1) minimum intake of fresh water of the lowest possible quality commensurate with sound technologic practice; (2) optimum recirculation (3) proper treatment before discharge; and (4) substitution of air cooling for water cooling.

Jan 1, 1965

By J. E. Dooley

A mass spectral scheme of analysis was devised which can be used to identify individually a single compound from a larger group of similar compounds. Mass spectra for 32 alkyl aryl sulfides are provided for future reference work, and analytical correlations used in producing the analytical scheme are discussed. Some of the correlations show that base peaks are either the same mass as the parent peaks or may be derived from cleavage alpha to the sulfur atom with migration of one hydrogen to the sulfur atom. Other spectral consistencies provide means of separating ortho-, meta-, and paratolyl arrangements in an overall analytical scheme. Determinations of chain lengths and separation of isomeric species are also discussed.

Jan 1, 1972

By John K. Owens, Wayne L. Howie

Mobile roof support (MRS) machines are used as roof support during pillar recovery in retreat operations in lieu of wooden posts, cribs, or hydraulic props. A Mine Safety and Health Administration-permissible load rate monitoring system was developed for the MRS by researchers at the Spokane Research Laboratory of the National Institute for Occupational Safety and Health. The system uses a dedicated embedded processor to monitor changes in pressure inside the hydraulic cylinders of the MRS through multiplexed data acquisition channels and converts these pressure changes to load rates that sequentially activate three load-rate-indicator lights mounted on the machine. Each light represents a different loading rate to alert mine personnel to dangerous conditions during pillar extraction.

By V. Ferrari

This report documents the three-phase program to design, fabricate, test, and demonstrate economical and practical methods of reducing noise levels on underground coal mining portal buses (mantrip vehicles). The noise-control treatments applied to a production-model portal bus were as follows: ? Wheel/rail vibrations were isolated from the vehicle frame by inserting elastomeric materials between suspension components. ? Vibration-induced noise was reduced by replacing all large sheet metal panels (except floor plates) with damped steel panels. ? Motor noise was reduced by tight-fitting covers made from damped steel and lined with sound-absorbing material, and by elastomeric motor mounts. ? The standard spur gears used in the traction drive system were replaced with helical gearsets. The program achieved the goal of reducing the average sound-level to below 85 dBA for typical operating conditions.

Jan 1, 1981

The Federal Coal Mine Health and Safety Act of 1969 requires that each operator of a coal mine shall take accurate samples of the amount of respirable dust in the mine atmosphere to which each miner is exposed, a measure designed to prevent the development of coal workers' pneumoconiosis. This textbook manual is used in the training of personnel to operate respirable dust sampling devices and to conduct sampling programs. It contains the portions of the act applicable to respirable dust standards, the procedures to be followed to insure compliance with Federal regulations, and descriptions of sampling devices.

Jan 1, 1971

The principal activities of the Bureau of Mines Explosives Research Center from July 1, 1962, to June 30, 1963, are described briefly in part 1. Part 2 gives short abstracts of publications that appeared during fiscal year 1963; in general, the research reported in these publications antedates the report period.

Jan 1, 1965

By S. P. Kinney, P. H. Royster, T. L. Joseph

"The study described in this paper, on the reactions in an iron blast furnace, is part of the investigation being conducted by the Bureau of Mines on combustion of coke and the reduction of iron oxides in the blast furnace. Previous study of the combustion zone of the iron blast furnace, by means of a series of as samples taken through the tuyeres across the hearths of 13 blast furnaces, showed that the combustion of the coke in the blast-furnace hearth is complete at a distance of 32 to 40 inches from the nose of the tuyere, measured horizontally toward the center of the furnace. The results of this previous work are sum¬marized in the curves shown in figure 1, where it will be noted that practically all of the oxygen disappears at a distance of approximately 30 inches from the nose of the tuyere.In order to determine the height at which oxygen is found in a vertical direction above the tuyeres - it had been suggested that the combustion zone turned upward near the tuyere and to obtain comparisons with the samples taken at the Bureau of Mines experimental6 (5-ton) blast-furnace at Minneapolis, the Bureau extended the gas sampling on a commercial furnace to a number of planes between the tuyere level and the stock line. The sampling was conducted on a 300-ton furnace, making foundry iron, operated by the Central Iron and Coal Co., at Holt, Ala. The furnace was smelting Southern red and brown ores and nodules from pyrite sinter. Figure 3 is a vertical section of the furnace showing the six planes sampled."

Apr 1, 1926

This report provides the results of an industrial engineering study that assessed the safety and efficiency of underground ore handling in U.S. metal mines. One of the primary findings of the study was the improvement needed in controlling muck size in the ore handling stream. Oversize ore causes much additional labor, creating work stoppages and is a principal cause of accidents in metal mines. This report includes data on block caving, back cut and fill room and pillar, shrinkage stoping, and sublevel stoping.

Jan 1, 1974

A compilation of papers presented at the Fourth WVU Conference on Coal Mine Electrotechnology in Morgantown, West Virginia, on August 2-4, 1978. Papers cover areas of electric power, electronic communications, detection and location of trapped miners, and electronic sensors and monitoring systems.

Jan 1, 1978

By J. F. Barkley

Smoke abatement is a subject of which fuel technology, although absolutely essential, is only a part. Its successful accomplishment starts and ends with human factors that must be given thorough consideration; between this "start" and "end" fuel technology is applied. Smoke abatement usually starts from the desire of some person or persons to be free from uncleanness caused by the stack of someone else and ends with the sincere desire of the operator of the fuel-burning equipment to maintain a clear stack. Although "smoke abatement been discussed for many years, it is only recently that the public has been mindful of such expressions as "air pollution" and "air hygiene." The subject has duel in common with that of supplying pure water but is more complicated. The public desires pure water, expects pure water, is willing to pay for pure water, and expects to continue to pay for it indefinitely; it is a development of civilization. It is doubtless correct to say, however, that people in general do not et realize the detriment of air pollution to their well-being or give the question enough serious consideration. This is illustrated by the fact that in city smoke abatement it is the mass of small householders that sins the most and is the hardest to handle. It is rather difficult to assemble a group of people in a room without the air becoming contaminated with smoke. Smoke abatement will lag with the lack of desire for pure air - probably the biggest human factor involved in its accomplishment.

Jan 1, 1939

By John R. McWilliams

This is one of a series of reports being published by the Bureau of Mines on mining methods and costs at various mines throughout the United States. Including the Holden mine in this series is particularly appropriate at this time. The mine was operated on a low-cost, large-scale production basis to compensate for low-grade ore. Even with the best conditions and the most efficient methods, the margin of profit was small. Under the present situation of rising costs and lowering metal prices, the profit margin vanished. On June 28, 1957, the mine operations ceased; therefore, this report can review the entire life span of the mine.

Jan 1, 1958

By W. G. Freeman

This study provides recommendations for improved safety in underground blasting procedures based on in-mine observations of blasting practices in 30 underground metal, non-metal, and coal mines, and the analysis of blasting accidents since 1970 and existing state and federal regulations pertaining to the storage and use of explosives. Results of these analyses and observations indicate that 1) blasting accidents have declined but are an important contributor to the hazards of underground mining; 2) existing regulations are essentially adequate; 3) greater emphases should be placed on human errors and unsafe practices and the enforcement of existing regulations; and 4) future revisions of these regulations and standards should be organized, and their intent coordinated to eliminate ambiguities.

Jan 1, 1980