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By J. F. Burr, D. P. Snyder, G. W. Luxbacher

"The Mine Improvement and New Emergency Response Act (MINER Act) of 2006 (PL 109-236, 2006) established the Office of Mine Safety and Health, functioning as the Office of Mine Safety and Health Research (OMSHR) within the National Institute for Occupational Safety and Health (NIOSH) and provided authority for awarding contracts related to the development and implementation of new mine technology and equipment. The OMSHR external contracts program was formed in accordance with the MINER Act and has since issued more than 150 contracts focused on worker health and safety. Initial funding for this program was provided by the United States Congress through two emergency supplemental appropriations and was focused on emergency oxygen supply, communications and tracking, and refuge chambers (also referred to as refuge alternatives). Since the MINER Act, Congress has continued to fund the program through the annual NIOSH mining appropriation. The program was supplemented starting in 2009 with an academic capacity building program directed toward developing university tenure-track faculty and facilities and supporting graduate students in the area of mine ventilation. Ground control was added as an additional focus area in 2011. A short synopsis of each contract is published on the NIOSH Mining website (www.cdc.gov/niosh/ mining/researchprogram/contracts/index.html) and final reports are available in digital form on request. A summary of the progress OMSHR has made over the 10-year period since the Act was published previously (Snyder et al., 2016).External contracts are broadly classified by the following areas:• Communications and tracking.• Emergency response.o Self-escape and breathing air supply.o Refuge alternatives.o Escape and rescue.• Equipment safety.• Fires and explosions.• Ground control.• Mine environmental systems (mine ventilation and atmospheric monitoring).• Worker/workplace health and safety.Contracts are issued under a request for proposal (RFP), through a broad agency announcement (BAA) or under an interagency agreement (IAA). An RFP solicitation includes a specific problem description and a well-defined scope of work to guide the offeror in preparing a bid to conduct the research. Under the BAA several problem areas are described and the offeror develops the scope of work and deliverables for the proposed research. An IAA is very similar to an RFP except it is a contract between two federal government agencies."

Jan 10, 2018

By Ronald S. Conti

This U.S. Bureau of Mines (USBM) report describes various fire-fighting resources available to the mining industry and examines the fire preparedness of four western coal mines. Information regarding fire-fighting equipment indicates that an inadequate maintenance program may cause component failure of fire extinguishers, damage to waterhoses is usually a result of improper care, and foam may be a convenient means of conveying water to the fire. Performance data relative to water nozzles (throw distance) and specific practices to improve the state of preparedness in many of these areas are discussed. Studies also indicated that a high-expansion foam plug, will travel down an entry, with a 1% rise in elevation, 207 m (680 ft) before a plywood stopping separating the generator and plug failed. The advance rate of the foam plug decreased when the entry is dry, requiring more foam concentrate and as the foam spread further down the entry. An examination of the mines showed state-of-the-art monitoring systems were common at the minesites. Fire safety was also stressed, including early detection and rapid response of the miners to evacuate the mine. However, the mines placed little emphasis on performance of water nozzles, or personal protective clothing for the underground firefighters.

Jan 1, 1994

By H. K. Shearer

Drilling for oil and gas in Arkansas in 1934 showed more activity than in any year since 1929; with a total of 96 completions, including 36 oil wells, 1 gas well and 59 dry holes. Of the producers, the lone gas well and 35 oil wells were in old fields, and one wildcat producer opened a new pool. Of the dry holes, 16 were in or near fields and 43 were wildcats. The total reported initial daily production of the oil wells was 9013 bbl., averaging 252 bbl. per well. Active drilling operations numbered 65 at the close of the year, compared with 26 at the beginning.

Jan 1, 1935

By Fernando O. Boechat

Com a redução da oferta de minério granulado de boa qualidade no mercado mundial e as restrições ambientais à sinterização, as pelotas de minério de ferro passaram a ocupar um papel importante como matéria prima para produção de ferro primário. Entretanto, embora apresentem maior resistência à degradação, as pelotas ainda sofrem com este problema, embora em menor magnitude, quando comparadas com granulados. Pode-se identificar a degradação das pelotas de minério de ferro em duas etapas, durante o manuseio e sob redução. Uma vez que vários estudos já analisaram a degradação durante o manuseio, a degradação durante a redução torna-se um assunto relevante e pouco explorado. Assim, o presente trabalho avaliou as energias envolvidas no movimento da carga ao longo de um forno de redução direta do tipo Midrex, usando o método dos elementos discretos. Para isso, foi utilizado o software EDEM® para obtenção das energias dissipadas durante as colisões das partículas. Aplicando estas energias ao modelo mecanicista proposto por Tavares e Carvalho [4] para fragmentação das partículas foi possível estimar a taxa de geração de finos no interior do forno. Estes resultados foram utilizados na previsão da degradação mecânica de pelotas no interior do forno, que previu a geração de 1,2 a 2,6% de finos gerados em um forno Minimod®, dependendo das premissas usadas.

Aug 1, 2018

By R. A. Cattell

The conditions under which the researches of the Bureau of Mines on petroleum and natural gas were conducted in 1952 were little changed from those indicated in the last report,2/ which dealt with activities during 1951, immediately after crossing of the 38th Parallel by the North Korean Army. Although only a small part of the program was classified in the military sense, there was a feeling of the clash of world forces which called for even cheer scrutiny of the research problems so that the emphasis could be placed without delay where the greatest needs for na¬tional defense seemed to be. The reports of the work accomplished were so directed as to have the greatest immediate value to persons charged with supply planning for the military forces and included information on the availability and characteristics of a wide variety of crude oils, fuels, and other petroleum products. Actually, the approach, direction, and conduct of the work do not differ greatly under the two circumstances, as has been pointed out in earlier reports; only the tempo changes.

Jan 1, 1953

By Louis R. Iverson

Patterns of species colonization, biochemical interaction among species, and competitive phenomena were studied in four reclaimed areas in western North Dakota ranging in age from one to four years after mining, along with a site from a native mixed grass prairie for comparison. Early successional changes in floristic composition and soil chemistry were quantified. The mined sites had been contoured, topsoiled, fertilized and seeded. Despite seeding of agronomic species, initial colonization was by fugitive species; analysis of the seed bank in topsoil showed that the most dominant colonizers immigrate after topsoiling. Of the 95 species encountered, Kuchia scoparia was the most dominant in the first two years following mining. Kochlo had relatively low densities in the first year (50-80 plants m-2), but was robust and attained heights of 88 cm with a biomass of about 400 g m-2 In the second year, the plant densities increased to over 10,000 plants m"2 but the height and biomass were reduced to 15 cm and 90 g m-2. However, during the third and fourth years Kochia density declined and was practically non-existent by the fourth year, while the planted Agropyron grasses had concomitantly increased. Other pioneers like Amaran thus retroflexus, Chenopodlum album, Helianthus annuus, Salsola spp. And Setaria spp. showed a less abrupt but similar decline. Chemical analysis of the soils over the same time period showed decreases in electrical conductivity (E.C.), and in the concentrations of P, Ca, Mg, Na, Li, Sr, and SO4 (due to leaching), while N increased. Field studies were conducted on the competitive relations between the dominant species - Kochia scoparia and Agropyron spp. - during early succession. It was found the Kochia acted as a "nurse" crop for several months during the first year of Agropyron spp. establishment, but then began to shade heavily by late July, thus reducing grass tillering. Field and growth chamber experiments on the intraspecific competition relations of Kochia demonstrated that its density and dry matter production, per plant and per unit area, conformed to several laws of plant population biology. Autotoxicity or the depression in growth of a species by its own degradation compounds, in Kochia, appears to be the main factor causing the decline in its growth. Results from a field experiment indicated that thinning dense second year Kochia stands to the density of first year stands did not alter the growth of Kochia, providing strong evidence for autotoxicity. Similarly, several growth chamber experiments demonstrated that small amounts of decaying Kochia leaves and especially roots were toxic to Kochia growth, but not Melilotus officinalis or Agropyron canlnum, Chemical analysis of the soils and plant tissues indicated nutritional im¬balances as shown by P/Mn and P/Zn ratios may be responsible for autotoxicity. In addition to Kochia, a bioassay experiment showed allelochemics to be important in several other colonizing species. Although our results indicate that later stage species generally have greater toxicities than first year colonizers, autotoxicity in the very initial stages seems to be accentuated by harsh habitat conditions. Several practices (mowing. fire, etc.) are used to manage grasslands. Mowing of the first year erect, annual, colonizing vegetation was shown to be beneficial in the growth and establishment of wheatgrasses after mining in western North Dakota. Plots containing Kochio predominantly were mowed in mid-and late-July, and in mid-August, during the first year of growth after recontouring, replacing topsoil. seeding and fertilizing. It was found the Kochia densities were reduced to two percent of the control and its biomass reduced to less than one-third when the area was mowed in mid-August. On the other hand, wheatgrasses showed increases of 23% in stem density and 860% in biomass production over the controls when mowed in mid-August. The mowing of Kochia just before seed-set apparently reduces interspecific competition between Kochia and Agropyron spp. during the following growing season. The method is highly recommended for use in hastening the establishment of planted grasses.

Jan 1, 1982

By George A. Laird

I. INTRODUCTION. THIS old and once famous district played, through its enormous production of silver and gold, an important part in the history of the State of San Luis Potosi. According to a pamphlet prepared under the direction of the Governor of the State, Sr. Don Blas Escontria, and presented to the visiting members of the Institute during the Mexican meeting of 1901, this district is situated 20 km. east of the city of San Luis Potosi, in a range of mountains of moderate height, extending 135 km. N. and S., and 16 km. E. and W.; and the mineralized area hitherto developed is about 600,000 sq. m. The history of the district,. as given by the record dated 1778, and formerly kept in the San Francisco convent, says that it was discovered in 1575 by Sr. Don Pedro Irarte, and adds that the city of San Luis Rey de Francisco del Potosi received its name (in allusion to the famous Potosi mines in Bolivia) by reason of the remarkable productiveness of its gold- and silver-mines in the first period of their exploration, during which they paid to the Crown, as " quintos " (the fifth part of the product), $97,000,000, as appears from the accounts of the royal treasury. The amount of the quientos paid during the " bonanza period " of 80 years was $72,000,000. The larger sum first mentioned probably represents a longer series of years. But either will suffice to indicate the great wealth of the mines. In 1663, the decadence of the industry began with the caving¬ in of several mines, concerning which the record of 1778, al¬ready cited, says, in substance, that on Good Friday one of the owners in the enterprise, in view of the unfavorable prospect of a lawsuit in which he was engaged, set fire to the timbers supporting the underground galleries and workings of the San

Jan 1, 1905

By R Norris, M Dunne

Substantial efforts by the industry, as well as by process and equipment designers, have resulted in many innovative developments that provide cost effective reductions in water usage. This paper showcases four emerging best practices in industry including examples of recent installations. Belt press filters are a small fraction of the operating and capital cost of alternative ædryÆ tailings technologies. This gives operators who must ædryÆ their tailings a competitive advantage and makes such operations much more sustainable. The new generation of belt filter presses use less energy, produces lower cake moistures and better disposal stacking properties. The need for tailings storage facilities may be eliminated or in some cases high-grade tailings can be dewatered and sold as a low value product. Mining applications include sand tailings, sinter plant waste, coal tailings and power station fly ash. Flip-flow screening machines are proven worldwide in the dry classification of coal and other minerals, reducing the size of beneficiation plants, whilst reducing energy, water demand and media consumption. They also allow the screening of wet/sticky materials not able to be sized using conventional screens. Lamella separators are used for toxic water clarification and/or sludge thickening in many downstream metal industries with the underflow often dewatered in a belt filter press. Such low cost, high capacity thickeners could also be used instead of conventional thickeners at smaller mines. The simple and reliable continuous washing upward flow (CWUF) sand filters have been used for treatment of waste water from coal preparation plants and steel works as well as in the production of potable water. The filtered waste water from mining processes can then either be reused or discharged from site. Other installations include cleaning mine water to prevent the blocking of dust suppression spray nozzles.

Jan 1, 2006

By J. M. Goris

Cable bolt supports are becoming an important ground control technique in underground mines in the United States and Canada. They show great versatility and are adaptable for use with many mining techniques, they have high load-carrying capacities, they can be installed in small areas with low roots, and they are cost effective. Investigators in a number of research institutes in North America have conducted studies to assess the material and support properties of cable bolts, evaluate their support capabilities under various mining conditions, and provide design criteria for using cable bolt supports as roof control systems under varying mining conditions. While conducting these studies, personnel have collected important information on the history, application, performance, and economics of these supports. This U.S. Bureau of Mines report documents this information so that ground control personnel unfamiliar with cable bolt supports can gain an understanding and appreciation of their use. A comprehensive bibliography of technical information on cable bolt supports was selected by the authors and is also presented.

Jan 1, 1994

By Mark K. Larson

Researchers at the U.S. Bureau of Mines have developed a FORTRAN computer program that can calculate stress states from overcoring measurements obtained from hollow inclusion cells, triaxial cells, strain gauges installed on the wall of a bored raise, doorstopper gauges, borehole deformation gauges, or a combination of any of these gauges. Such stress states are calculated with reference to global and principal coordinate systems. The background of the development of the program, its capabilities, and its special features, as well as the input required, are described in this report. Sample output is also shown in appendix C. Difficulties associated with numerical calculations of principal stresses and directions are pointed out. Threshold values for detecting these problems are reported; these values may be changed by the user as desired. Several test problems were set up to verify the computer program and were successfully solved.

Jan 1, 1992

By By Staff

"Acid mine drainage can be controlled by water treatment, retardation of the pyrite oxidation reaction system, or enhanced prediction that allows preventive action to be taken. The Bureau of Mines is conducting research in each of these areas; the results of this research are summarized in the eight papers that comprise this volume. Field work to evaluate overburden analysis, alkaline injection, and bactericidal control of acid formation is described, along with two new inexpensive methods to treat acid mine water. These papers were prepared for an acid mine drainage technology transfer meeting held in Pittsburgh, PA, on April 3 and 4, 1985. INTRODUCTIONAcid drainage from coal mines is one of the most persistent industrial pollution problems in the United States. Over 5,000 miles of streams and rivers are adversely affected, primarily by underground mines that have been abandoned for decades. Meanwhile, at active mining operations and at sites where mining occurred after 1977, discharge water must be treated to meet fairly stringent regulatory limits--at a cost to the industry of over $1 million per day.The Bureau of Mines has a special responsibility to facilitate integration of mining and mineral processing with environmental safeguards. This responsibility is twofold: the development of techniques to reduce or eliminate environmental degradation, and the improvement of existing pollution control processes to make them more efficient and more cost effective. Research in acid mine drainage exemplifies the Bureau's concern for these environmental aspects of mining.This collection of papers summarizes much of the Bureau's recent research on acid mine drainage and will give the reader a sense of where the research is headed, in addition to providing details regarding new technology and recently acquired knowledge. The research papers address four basic objectives:"

Jan 1, 1985

By J. A. H. Church

The report is too voluminous to be considered in detail within the scope of a single paper, so I will confine my consideration of it to the broader aspects, leaving other members to deal with points of particular interest. The method of presentation leaves one with an uneasy sense of prolixity and confusion of thought; the foreword by the Chairman may well be accepted as a true index of the whole. His argument amounts to this: Recognizing at the outset the futility of divided counsels, it was deemed advisable to arrive at unanimity. To this end, some members subscribed to views to which they do not whole-heartedly assent, thus giving weight to conclusions with which they were at variance. Unanimity cannot be qualified-either it exists or is absent-and, moreover, in the text of the Com-mission I can find no word that unanimity is required. Surely it would have been preferable to have a unanimous report covering such aspects as were acceptable to all members, with minority reports by individual members on such other aspects as were controversial, leaving it to the Government to give such weight to the divergent views as the personality of their sponsors might warrant. In the final analysis the value of an opinion varies directly as the personality of its exponent.

Jan 1, 1926

By George A. Burrell, G. W. Jones, Frank M. Seibert

In this bulletin, the style of Bulletin 42 has been closely followed. Much of the material is reprinted on the following pages in its original form, and changes have been made only where manifestly neces- St,ry. Laboratory methods have been brought up to date. Some types of apparatus described in Bulletin 42 have now become obsolete and newer designs are described instead. The authors hope that this bulletin will be of as much service as was Bulletin 42.

Jan 1, 1926

By John Ellenberger

The National Institute for Occupational Safety and Health (NIOSH) has collected pillar and span data at 34 stone mines in 10 states to develop pillar and roof span design guidelines for underground stone mines. Pillar, floor and roof conditions each contribute significantly to the overall mine stability. The roof may be stable for a century, or it may appear to be stable but fail with little warning. Clearly, an assessment of the mine roof is critical to the safety of these operations. However, up until now, the assessment of the mine roof came primarily from exposures in roof falls or portal areas. This provides only limited information, and a more proactive approach is needed to assess changing mine conditions. A separate effort was undertaken to examine the roof structure with the use of a borescope. Numerous physical and geologic roof structures were observed with a stratascope/borehole video camera. The objective of this work was to develop a technique of assigning numerical values to features seen within the mine roof and apply those values to formulate a roof stability evaluation. Such features as changes in color, grain size, and general lithologies are readily observed. Minor structures in the rock, fossils and fractures are also readily identified. Each feature may have a variable and site-specific impact on roof quality. A number of mines were visited and a series of holes were borescoped in each mine. The features identified in the roof were classified and potential for roof damage related to each feature was assessed. A process is presented that relates the structures and their locations to provide a numerical value, or roof quality index that can be used to assess roof stability.

Jan 1, 2009

By Edward L. Beutner, Robert M. Crump

Benson Mines low-grade iron ore reserve is a replacement deposit within the Grenville gneisses of the Adirondacks. The average grade of the crude ore is about 23 per cent iron. The iron minerals are principally magnetite and hematite disseminated throughout the gneisses as discrete grains about 1 mm in size. Both the ores that are beneficiated by magnetic means and the non-magnetic ores that are treated by a gravity method of concentration are found in stratigraphically different positions but are mined from one open pit, which is about 2.5 miles long and 800 feet wide and are treated separately. The gneisses are described and named according to the distinctive mineralogy of each. Recognition of the gneissic types permits the interpretation of the structure as a northward-plunging syncline overturned to the west. A large subsidiary anticline-syncline complex occurs on the east limb of the major syncline. Iron minerals in sufficient quantity to be considered ore are confined to areas where the footwall rock has been overturned to become the hanging wall.

Jan 1, 1968

By Edmund S. Leaver, Charles E. Van Barneveld

In response to numerous requests from metallurgists and operators for information regarding the status of the sulphur dioxide leaching process , developed at the Southwest experiment station of the U. S. Bureau of Mines , Tucson , Ariz . , the following statement has been prepared . A more complete report is now in course of publication and will appear as Technical Paper 312. This process was devised to provide a cheap and efficient method for treating the so- called "porphyry " copper ores of the Southwest which generally contain both " sulphide " and "nonsulphide " copper minerals , mixed in such proportions that they can only be satisfactorily treated by a method which will concurrently recover both the sulphide copper and the nonsulphide copper . The latter term has been adopted to include all the minerals commonly referred to in operating phraseology in the mills of the Southwest as " oxidized" , " oxide " , or " soluble " copper . confident that the sulphide dioxide leaching process , as developed by us with the cooperation of the Miami Copper Co. and the Arizona Copper Co. , is suitable and commercially available for a wide range of ores .

May 1, 1922

By Peter Price

Introduction The Horne mine, the property of Noranda Mines, Limited, has in the last six years become one of Canada's leading gold and copper producers. Since the smelter was blown-in during December, 1927, up to the end of 1933, it has produced approximately 1,200,000 oz. of gold and 35O,OOO,OOO lb. of copper. The property is situated within an area occupied entirely by pre-Cambrian rocks and characterized by the complexity of rock types and structures common in such terrain. But apart from this the mine also presents other features of unusual interest in the size, number, and variety of the ore-bodies, the mineralogical associations, and the rather exceptional values both in gold and copper. It is not surprising, therefore, that a study of the geology of the mine should bring to light many interesting problems. The present paper summarizes, as concisely as possible, the results of such a study. Actually, it is a much abridged version of a more comprehensive and detailed paper completed by the writer a year ago (1), but embodying certain corrections and additional data made possible as a result of further development at the mine and of field work carried out during the summer of 1933. Owing to limitations of space, the paper is, in the main, a presentation of conclusions arrived at in the course of the study. Much of the supporting evidence cited in the thesis referred to has, of necessity, been omitted here.

Jan 1, 1934

By Phil Shelton

What exactly does clean coal mean? Mining coal creates dust and releases methane gas. And burning coal liberates CO2 and emits particulates, including SO2 and NOx. Coal creates wastes that are often stored in unsightly and potentially dangerous slag heaps and lagoons. When clean coal technology is discussed, it sometimes seems that creating modern or ?ultra super critical? coal-fired power stations is presented as the main or even the only answer. However, there may be a more holistic approach. Using the energy potential of coal is always going to have environmental impacts. Some of these will be negative. But the need to secure future energy resources demands that society tackle these negative issues and find ways to minimize and offset them.

Jan 1, 2010

By Ergin Arioglu, Werner Burger

"SUMMARY The Istanbul Strait Road Crossing Project includes a 3.34 kilometer subsea tunnel excavated by TBM with an excavation diameter of 13.71 m. The tunnel will incorporate two road decks, each employing two traffic lines and shoulder with the daily capacity of 100,000 light vehicles. The tunnel alignment crosses full face rock sections with heavily fractured zones due to tectonic events as well as a long central stretch of difficult mixed face and very variable soft ground conditions. The demanding ground conditions and the large diameter in combination with realized face pressures well above 10 bar required a highly specialized and well adapted TBM. The paper describes the project challenges and the related technical solutions incorporated within the TBM design as well as the real site experience. INTRODUCTION In 2013, a 13.71 m diameter Mixshield was manufactured in Germany for the Istanbul Strait Road Crossing Project. The delivery of the TBM in late 2013 was a major milestone for the Istanbul Strait Road Crossing Project, also known as the Eurasia Tunnel Project. The Eurasia Project (www.avrasyatuneli.com.tr/en) consists of a 14.6 km route including a 5.4 km tunnel segment in its central part crossing the Bosphorus. The 3.34 km subsea section of the tunnel was excavated in closed mode using a Mixshield TBM. The remaining tunnel length is constructed by sprayed concrete lining (SCL) method followed by a cast in place (CIP) lining or by cut and cover (CC) structures for the TBM transition boxes (Figure 1, right). Other project sections on the European and Asian side consist of upgrading and widening surface access roads towards the tunnel. Conceptual ideas of connecting Asia with Europe via a tunnel crossing the Bosphorus have been around for an extended time and only became realistic towards the end of the 20th century based on significant technical developments in mechanized tunneling. Feasibility studies for a new Bosphorus crossing in 2003 and 2005 confirmed and suggested a road tunnel in its present alignment as the preferred solution. Following an international tender process the Ministry of Transport, Maritime Affairs and Communications of Turkey assigned ATAS, a special purpose company formed by Yapi Merkezi (Turkey) and SK E&C (South Korea), to design, build and operate the Eurasia Tunnel Project. The Implementation Contract was signed in February 2011. In 2012, Herrenknecht AG was selected as the supplier for the 13.71 m Mixshield TBM."

Jan 1, 2016

By John Craw

This paper has formulated the methods, both medical and engineering, for the control of pneumokoniosis in the haematite-mining industry in West Cumberland, but this is only part of a general service to improve the lot of the worker in these mines, to make him a better and happier workman, and to permit him to enjoy his work and leisure in comfort and good health. This organization has now been functioning for more than ten years and the results are indeed heartening, but it is only as a result of constant vigilance from the mining and medical point of view that such a plan can operate efficiently. The human element and its full understanding is by no means the least of the problems.

Jan 1, 1947