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By J. Bruce Clemmer

[Gypsum is one of the mo .. t iJf.l)ortant nonmp.tal1.ic T!1inerals, as is indicat-? ed by the fact that tlle Uni ted states cO!1sUl:Ied p, roximn..tely 3,500,000 tons of natura.l and calcinecl e::,j;-psum in 1937. The b\.'.ilr:.in.; traces \"fe.ro the largest users and required 2,520,000 tons of calcine for the r-roductiop. of plaster,]

Jan 1, 1941

By John S. Hutchins

Two potential modified in situ methods are described for recovering the 68% "unrecoverable" hydrocarbons in oil reservoirs. For the 300 billion barrels of conventional light crude a Drip Drainage system is suggested by mining underneath a reservoir and producing from below by controlled gravity flow. For the 200 billion barrels of heavy or viscous oil and tar sands deposits a Flip Flop process is described using surface flooding with hot water saturated with surfactant and weighting additives. Mining engineering description of shafts and tunnels required are included as is discussion of the tunnel proximity to a reservoir. Petroleum engineering flow equations to describe production rates and candidate reserve areas of the U.S. are described. DCF economics are provided to indicate that current oil prices may be sufficient to commercially develop these recovery methods.

Jan 1, 1978

By C. B. Manula

Bituminous coal mining in the United States is currently experiencing a period of rapid growth which began in the early 1960's. Future demands are conservatively predicted to rise to 700 million tons by 1980 and to anywhere between 1 to 3 billion tons by the turn of the century. This means a continuous expansion of coal production by a factor of at least two can be expected before the end of the century. Over the last few years, production from underground mining has decreased; yet it is about 50% of the total coal output. In the absence of any discovery of near surface coal deposits, and even after conceding that some deeper deposits can be surface mined with changes in technology it can be reasonably assumed that coal production from underground will continue to play an important part in solving the energy crisis.

Jan 1, 1975

By John W. Mentz

Phase I study efforts addressed: 1) acid mine drainage formation theory; 2) effects of inundation in reducing acid mine drainage formation; 3) summary information on the types of acid abatement technology currently available and the problems inherent in each; 4) analysis of two potential means of partially inundating abandoned segments of active underground mines to reduce acid formation. This subsequent Phase II Draft Final Report addresses all of the above, but concentrates on and defines Item 4. Seal construction techniques were taken through five logical steps as follows: A) Location Analysis; B) Coal Barrier Pillar Analysis: C) Ground Water Analysis; D) Design Considerations: E) Economic Analysis. The design details of both low wall dams and section seals were discussed in a series of segments: a) Case Histories; b) Feasibility Analysis; and c) Design (including representative calculations). Study efforts showed that both concepts are feasible only in certain mines where the geologic-hydrologic physical makeup is suitable to contain a mine pool. Low wall dams in particular were found to have extremely limited applicability as a means of pollution reduction. Section seals, while clearly dependent upon site specific conditions, have a some what broader range of utility and are more effective in pollution reduction. The proven dramatic reduction in acid mine drainage attributable to inundation makes this a concept that must be considered.

Jan 1, 1981

By John C. Edwards

A computer program, developed for the Bureau of Mines under contract, predicts in a quasi-steady-state approximation the ventilation and contaminant concentrations and temperatures when a fire occurs in a multi-level mine. For periods of time in which there is no significant change in the ventilation, yet a fire is producing fumes, a real-time fume concentration throughout the mine is calculated. Multiple and time-variable contaminant sources can be simulated. Recirculation paths that can develop provide a mechanism for increasing the fume concentration in the mine network and are identified by the computer program. This report contains a listing of the Fortran computer program as well as the required format of the input data. Two examples are provided of the real-time spread of smoke from a fuel-rich fire throughout a multilevel mine. The first example considers an operational exhaust fan as well as a booster fan. The second example evaluates the real-time smoke spread following a failure in the exhaust fan; recirculation occurs in this latter case.

Jan 1, 1982

By Michael T. Nigbor

This Bureau of Mines publication identifies the significant environmental issues associated with the potential development of strategic and critical minerals in the Stillwater Complex, MT. The Stillwater Complex contains deposits of Cr, platinum-group metals (PGM), and Ni. Issues that must be addressed prior to minerals development include the effects mining, milling, and smelting will have on the land, water, and air, and methods of minimizing the environmental impacts.

Jan 1, 1985

By Ralph H. Whaite

To assist the anthracite industry obtain technical data on pneumatic packing, the Federal Bureau of Mines imported a pneumatic packing machine from Germany and installed it in a mine of a cooperating company in the Northern anthracite field of Pennsylvania. This report covers the second in a series of experiments in applying pneumatic packing for controlling strata movement (subsidence) above mine workings in the Pennsylvania anthracite region. The first experiment2/ was begun in January 1950, in a section of the mine where about 50 percent of the original coal remained in the form of pillars; since the company did not plan to mine the pillars in this particular area, pneumatic packing of the chamber voids was done for test purposes only. During this initial test the machine was operated on 204 shifts, and 652,400 cubic feet of breaker refuse material (22,834 tons) was packed into the voids of 16 chambers. The work was completed in December 1951.

Jan 1, 1956

By Robert F. Randolph

Introduction This paper is a descriptive analysis of injuries and fatalities at small surface bituminous coalmining companies in Pennsylvania. The purpose of analyzing a specific industry sector and location is to identify issues that might be missed in a wider analysis. Other studies of small mine safety (e.g., Peters and Fotta, 1994, Randolph and Boldt, 1997) have shown that the relationship between safety and mine size is not a simple one. Some injury types occur at higher rates at small mines, while others occur at lower rates. Consequently, an analysis limited to a specific type of mining can help identify hazards and issues specific to that sector. The results of this analysis will be useful for directing training, intervention, and research efforts towards the most prevalent causal factors and incident types. Procedures and Definitions Data sources The primary sources of data for this analysis were files provided by MSHA containing information collected under Title 30 Code of Federal Regulations, Part 50. These files, commonly referred to as “Part 50 data”, are provided though MSHA’s Program Evaluation and Information Resources directorate. Two primary types of injuries were selected from the Part 50data: Fatalities (MSHA “degree of injury” code 1) and lost-time injuries, otherwise known as nonfatal with days lost (MSHA “degree of injury” codes 2 through 5). Lost-time injuries involve either actual days away from work or days of restricted activity or both. Fatality and lost-time injury incidence rates were calculated using the standard MSHA formula: Number of injuries per 200,000 employee-hours. Additional information on company sizes and mine ownership was provided by the Pennsylvania State University College of Earth and Mineral Sciences. Time span A five-year time span was selected for this study. More than a single year of safety experience is usually needed to capture a broad range of incident types. Many types of injuries, especially fatal injuries, can be extremely rare, and may be missed if too short a time span is selected. However, a time span that extends too far back may begin to suffer historical threats to validity. That is, incidents that occurred several years ago may be caused by hazards that have since been remedied or may be related to mining practices and conditions that no longer exist. A five-year span offers a practical compromise between these two concerns. Consequently, the MSHA Part 50 data files from 1993 through 1997 were used. The 1997 file was in “preliminary” form at the time of the study, so small variations from the final 1997 “close out” file can be expected. Based on past experience, we do not expect the close-out variations to have a significant impact on the findings.

By L. C. IlsLey

The theory and practice followed by the Bureau of Mines in investigating electrical equipment4/ made for service in gassy mines are of particular interest not only to manufacturers but also to those organizations that deal with safety anal inspection at the mines. This publication purposes to discuss the theory upon which tests of equipment in explosive atmospheres are based and to consider inspection and other matters pertaining to investigations made by the Bureau in ascertaining whether a machine merits approval. The material in this report is taken from an earlier bulletin,5/ which is row out of print, and has been revised and brought up to date to make the information again available to manufacturers, inspectors, and others interested in the development of safe equipment.

Jan 1, 1954

By Horace C. Porter

Much has been written of the changes undergone by coal in storage and the deterioration of coal through exposure to the weather. In order to obtain definite information for the benefit of the Government departments and of all who store coal in large quantities, a series of tests was begun in the fall of 1909 under the supervision of J. A. Holmes, then chief technologist of the United States Geological Survey, and was continued by the Bureau of Mines after its establishment in 1910. The tests were confined to determinations of the loss in heating value of the coals and did not include a study of other deterioration; for example, in coking quality or the yield of by-products in coking. The Bureau of Yards and Docks of the Navy Department cooperated in tests of New River (W. Va.) coal, a variety largely used by the Navy. A preliminary report presenting a brief account of the early results of these tests has been published by the Bureau of Mines as Technical Paper 16.a The detailed report is presented in this bulletin, which gives a full account of the tests and the analytical data covering a period of five years' storage. Data of somewhat similar experiments for shorter periods with gas coal from the Pittsburgh bed, with Pocahontas coal on the Isthmus of Panama, and with Sheridan, Wyo., subbituminous coal, which is used for railroad and other purposes in the West, are included.

Jan 1, 1917

By Harold W. Lipper

BUREAU OF MINES helium plants produced a. record-breaking 477 million cubic feet of this essential element in 1959. The supply of helium was less than the demand before operations were resumed at the Navajo plant in July and begun Sit a. new plant at Keyes, Okla., in August. Helium was in abundant supply after August, and the informal allocation system which had been in use intermittently since 1955 was discontinued Delivery of 26 new tank cars in August and September increased the total in the tank-car pool to 163. Defense and space agencies and the Atomic Energy Commission continued to use more helium in their operations and research.

Jan 1, 1960

By Richard C. Barth

Fourteen field plots were established at active coal mines in the Northern Great Plains. A wedge was cut into spoil and backfilled with soil; soil depth ranged from 0 to 152 cm over a linear distance of 15 m. Perennial grasses were planted in each plot, and production was measured from 1978 to 1981. Based on spoil traits and biomass response patterns, plots were grouped into four types. Spoil for Type I plots was near neutral, slightly saline, nonsodic, and clay loam in texture. Perennial grasses reached maximum production with approximately 50 cm of soil depth. Spoil for Type II plots was characterized as sodic and fine textured; soil-depth requirements averaged 83 cm for maximum production. Spoil for Type III plots was characterized as strongly acid, and production increased throughout the soil depth range tested. Spoil for Type IV plots was similar to soil in chemical and physical traits; there was no production response to soil depth. Soil depth requirements were also dependent upon precipitation and species. In general, soil-depth requirements decreased in dry years and with use of introduced species. An appendix contains data evaluations on an individual plot basis.

Jan 1, 1982

By W. P. Yant, G. W. Jones

"Introduction.During the past two years the Bureau of Mines has conducted a study of natural-gas heaters*** to determine (1) what types of heaters literate carbon monoxide; (2) why carton monocide is liberated; and (3) how, by change of design or construction, the liberation of this gas can be largely eliminated, In addition to the above study the bureau has investigated cases in the Pittsburgh dis¬trict where fatalities have resulted from carbon monoxide given off by natural-gas heaters.Since these fatalities were first brought to the attention of this bureau through the press, it is likely that some cases were missed and thus not listed. On the other hand, some cases reported as being due to carbon monoxide poisoning, on investigation were found to be due to causes other than carbon monoride.The cases listed herein were shown in all probability to be due to carbon monoxide. Those in which there is any doubt have been omitted; so have those in which there was part asphyxiation, where the victims later recovered."

Feb 1, 1924

By James L. Elder, J. P. Capp, James J. Dowd

The Bureau of Mines and the Alabama Power Co., jointly, conducted the first experiment undertaken in the United States in underground gasification of coal in place, at Gorgas, Ala. Milton H. Fies, manager of coal operations, Alabama Power Co., proposed the cooperative investigation to Arno C. Fieldner, chief, Fuels and Explosives Branch, Bureau of Mines; and assisted in supervising the experiment. The objectives of the experiment were to determine whether coal in place could be burned successfully and whether the burning could be controlled; the effect of the fire on the coal bed and the overlying strata; and the yield and quality of gas that could be obtained.

Aug 1, 1947

The selective placement of coal strip mine overburden is examined. Physical end chemical properties of spoil detrimental to revegetation and groundwater are detailed. The United States is divided into regions of similar problems. Five mining methods already used in the industry, that are capable of selectively handling; waste are examined in detail. Technical and economic comparisons are made for the systems when applied to realistic mine settings. The same analysis is conducted for five novel methods capable of selectively handling waste. Comparisons arc made between novel and existing methods. Suggestions for new and modified equipment are outlined. Recommendations for further research are provided.

Jan 1, 1981

By Michael Rieber

A new mode of coal transportation based on the principles of pneumatic conveying has been recently, proposed by Soo, et al. [5]. Pneumatic transport is not a novel concept and commercial experience with pneumatic pipelines for short haul distances is plentiful. The list of applications is long and includes transporting ores, chemicals and pharmaceutical products, agricultural products, and domestic and industrial wastes. The study by Soo, et al. [5] updated an earlier one [l0] and presented the most recent economic evaluation of pneumatic transportation of coal. Their preliminary study concluded that there are immediate advantages for short-distance transport (less than 100 miles) and that it is both technologically and economically feasible. That study also concludes that pneumatic transport has a higher potential and more promising profitability in long-distance applications than rail if new track and roadbed must be built. Some of the advantages of long and short distance pneumatic pipeline transport of coal compared to rail and slurry transport are: 1) Replacement of diesel fuel consumed by unit trains, as the pipeline can be powered by coal-generated electricity; 2) Reduction of the skilled-labor costs required for upgrading and maintaining railroads; 3) Elimination of signaling, rerouting and overpass costs due to increased rail traffic on' mainline trackage;

Jan 1, 1977

By Pablo Velasco

The Belize economy recorded modest growth during 1980; the growth of the gross domestic product (GDP) in real terms was between 1% and 2%. At current prices, the 1980 GDP reached $108 million2. This output was largely attributed to the performance of a few industries, mostly nonminerals. Such performance improved significantly the balance of payments situation by reducing the deficit from $19 million in 1979 to $4 million in 1980. The rate of inflation was an estimated 18% in 1980 and would have been greater if not for a conservative monetary policy and price control on a number of essential items. Expert earnings increased $43 million, or 50%, from the 1979 level. After increasing more than 25% in 1979, imports increased only 6% in 1980 to a level of $141 million owing to the decline in investment and stabilization of petroleum prices. The balance of trade deficit was $9.8 million in 1980, a marked improvement from the 1979 level of $45.1 million. The mineral output for Belize accounted for only a fraction of 1% of the GDP. Such activity was limited to the production of limestone, marl, and sand and gravel, all of which were primarily used in construction of the Northern Highway between Orangewalk and Belize City. Mineral resources are deficient or nonexistent in Belize for the majority of metals and nonmetals, although the Government and others continue to believe that petroleum must exist in Belize. The proximity to Mexican oilfields and the growing finds in the Peters area of Guatemala support this expectation. The Government continues encouraging exploration onshore and offshore and offers terms that

Jan 1, 1982

By T. F. Curry, L. B. Berger, H. A. Watson, S. J. Pearce

The conduct of work at elevated air pressures , such as in caissons and in tunnel - driving in subaqueous strata , poses safety problems not encountered in mining and tunneling operations at ordinary atmospheric pressure . This publication discusses some of the problems involved and presents information on the following subjects : ( 1 ) Physiological effects of gases at elevated pressure . ( 2 ) Use of respiratory protective equipment in rescue or recovery operations in event of fire or other emergency in pressurized tunnels . ( 3 ) Effect of elevated pressure on performance of some gasdetecting instruments ; interpretation of the results . Various types of respiratory protective devices are discussed in relation to their possible use at elevated pressures , especially the 2 - hour , selfcontained , recirculating - oxygen - breathing apparatus , which has had wide use in the United States during rescue and recovery work in the mining industry . A modified procedure that eliminates the hazard of oxygen poisoning enabling the safe use of this apparatus at elevated pressures , up to 45 pounds per square inch , gage , and tests to verify its practicability are described . procedure involves control of the partial pressure of oxygen in the breathing

Jan 1, 1964

By Henry P. Wheeler

H ELIUM (chemical symbol: He) is a member of a family of normally gaseous elements, which, because of their zero valence and corresponding lack of chemical activity, are called the "noble" or "inert" gases. It is a monatomic element with an atomic number of 2, and it exists naturally in two stable isotopic forms-He3, with an atomic mass of 3.0170, and He4, with an atomic mass of 4.0039. With the exception of a trace (10-6 percent) of He3, all of the naturally occurring helium is He4. Two unstable isotopes-He5, with atomic mass 5.0137, and He6, with atomic mass 6.0208-are listed by various scientists, but the existence of He5 is questioned by some of them. He6 is radioactive, with a half-life of 0.8 second. Helium was discovered in 1868 in the gaseous atmosphere surrounding the sun. Although several scientists studied the solar chromosphere that year, it is generally agreed that J. Norman Lockyer of England should be credited with the discovery of helium, which he named, deriving the word from "helios," the Greek name for the sun. It was not found on earth until March 1895, when William Ramsay of London produced a small amount from a sample of cleveite, a uranium-bearing mineral. In 1905, H. P. Cady and D. F. McFarland of Kansas found helium in natural gas produced from a well near Dexter, Kans., and for the first time a large source of helium became available.

Jan 1, 1952

By S. J. Page, R. A. Jankowski, J. A. Organiscak

The U.S. Bureau of Mines investigated the relationship of bituminous coal seam parameters and the amount of airborne respirable dust generated at longwalls. Dust and coal samples were obtained from 20 longwalls operating in geographically representative coalfields throughout the United States. Statistical analyses of coal seam parameters and airborne respirable dust measurements indicate a likely causal relationship between seam type and respirable dust. Low-ash, high-volatile coal seams were associated with higher airborne respirable dust levels. A negative linear correlation (significant at the 95-pct confidence level) was observed between the seam's ash content and airborne respirable dust, explaining up to 18 pct (R2 = 0.18) of headgate dust level variation and up to 15 pct of tailgate dust level variation. Volatile matter was found to have a positive linear correlation with tailgate dust level, explaining 16 pct of the variation. Further data examination indicates that these relationships with dust are most likely nonlinear, because of improved R2 values over the linear correlations. However, a notable portion of longwall dust production is influenced by other operational parameters, so additional research under more controlled conditions is needed to determine the seam's causative functions.

Jan 1, 1992