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By R. Ward Stahl

Fire is still a scourge of the mining industry, although many precautionary measures have been and are being taken to reduce the incidence of fires and to combat them. Generally, the success of fire extinguishment is directly proportional to the speed of attack, and the speed of attack in turn is dependent upon the availability of materials and trained personnel. Preparations for firefighting are frequently neglected because they are considered emergency needs and do not contribute directly to coal production. Fire incites panic--a fact often overlooked--but such chaos can be minimized by training people in the use of equipment and procedures. Heat, smoke, and fumes hamper the approach to a fire; however, a relatively new technique of attacking fires with high-expansion foam may well contribute greatly to firefighting. The foam is transported to a fire and used at a considerable distance, thus permitting the firefighters to work more safely.

Jan 1, 1962

"The Antamina orebody is a geologically complex, polymetallic skarn located in the Peruvian Andes. A range of copper and copperzinc ores are campaigned separately through the concentrator producing copper and zinc concentrates as well as lead and molybdenum by-products.Ore type classification at Antamina is based on chemical assays; geological or lithological variations are not considered. Consequently, each ore type demonstrates a wide range of concentrator performance.Antamina is currently implementing a system to track ore movements from the shovel face to the concentrator. Relatively sophisticated models of run-of-mine and coarse ore stockpiles ahead of the mill will be used to account for the variable delay between mining and milling.One of the numerous benefits of ore tracking is the ability to directly associate the measured concentrator performance with a physical location in the orebody. Using existing mine planning software, three-dimensional models can be created of such performance measures as metal recovery, concentrate quality, operating cost, and reagent consumption.Such a database of information allows the true value of different ore sources to be determined. The value of an ore source is conventionally measured as metal content (individual or combined ‘equivalent’) with a cut-off grade applied to indicate some base level operating cost. However, the true value of an ore source should include dynamic factors like haulage cost, reagent use, smelter penalties, and even prevailing metal prices. If an ore source is considered from all perspectives rather than simply its potential to deliver value, the concept of ore becomes more flexible. Any ore source that reveals itself to be unprofitable can be eliminated from the mine plan or possibly blended with others to improve its value. The ability to predict mill performance, and thereby profitability, is a powerful tool.In an operation such as Antamina, where managing ore sources, campaigns, and the delivery of a variety of concentrates in a narrow timeline to customers is a daily challenge, prediction is the key to success and improved efficiency."

Jan 1, 2005

By M. Q. W. Jones

This paper presents a compilation of physical properties of rocks from the Bushveld Complex. The database consists of more than 900 measurements each of thermal conductivity and density. The data are well distributed from localities around the Complex and most rock types are well represented. Thermal conductivity and density are shown to vary widely in the ranges 1.8-4.2 W m-1K-1and 2600-4200 kg m-3respectively. Although only 190 heat capacity measurements are available, this parameter is quite uniform for most rock types present, 800-900 J kg-1K-1, except for chromitite, which has a lower average, 750 J kg-1K-1. Rocks encountered in deep platinum mines are particularly well characterized and this has important implications for prediction of mine refrigeration requirements. The heat flux into a semi-infinite region with properties typical of the Bushveld Complex as a function of time is substantially lower than an equivalent model for the Witwatersrand Basin.

Jan 1, 2015

By C A. Locke, A B. Christie, J Cassidy, J L. Mauk

New and existing gravity and aeromagnetic data are used to determine the structure of the Waihi region and to investigate any relationship between structure, hydrothermal alteration and epithermal mineralisation. The 24 mGal, 10 km diameter, negative Bouguer gravity anomaly which occurs south of Waihi has been modelled as a I.5 km deep asymmetrical basin. This basin, the Waihi Depression, is interpreted to be infilled with low-density volcanic rocks of the Uretara Formation and Whitianga Group, overlying older andesites of the Waipupu Formation. To the north and west, the margins of the depression are defined by the Waihi and Mangakino Faults, which have been modelled with dips of 45 - 60¦ to the south and west respectively. The southern and eastern boundaries of the Waihi Depression are defined by smooth, shallow dipping (15 - 20¦) boundaries. The Waihi Depression is interpreted as a fault-angle depression, resulting from southeast extension in the early Pliocene. The Waihi Fault is modelled as an approximately E-W feature, located to the south of Waihi. Small 2 - 4 mGal positive Bouguer gravity anomalies occur north and west of the margins of the depression, and correlate with known areas of hydrothermal alteration and areas of low magnetic gradient.

Jan 1, 2003

By S. C. A. Franca, M. T. Millqvist, A. B. Luz

Laboratory experiments were performed on a Brazilian diatomite from Bahia State to produce an industrial product for use as a filter aid. Bench and pilot plant tests were conducted consisting of: diatomite desegregation, organic matter and clay removal, filtration, drying and calcination. Calcination temperature and sodium carbonate addition influenced diatomite particle size distribution. Optimum filtration rates for calcined products were obtained at 900°C and 47 min. residence time with 3% (w/w) of sodium carbonate addition, and resultant products met specifications imposed on filter aids.

Jan 1, 2002

By William R. Yernberg

A conference on coalbed and coal mine methane was held March 27 and 28, 2000, in Denver, CO. The conference, organized by the Strategic Resource Institute, was attended by leaders in the coal mining and gas energy industry. The conference focused on the recovery of methane from coal beds as an energy resource and the removal and utilization of coal-mine methane (CMM) related to underground coal mining. The two-day conference discussed methane resources around the world, methods of recovery, methane markets, underground coal mining, health and safety issues and environmental issues related to methane. The consensus among the presenters is that the future looks promising for coal bed methane (CBM) and CMM.

Jan 1, 2000

By Franklin D. Cooper

This Bureau of Mines report reviews in detail the foundry coke situation in the United States in 1975. It discusses intrinsic production problems and identifies opportunities for modifying operating practices so that the quality and yield of foundry coke can be enhanced without unnecessary investment in new equipment. Major topics include operating data and attendant practices and problems, the relationship of carbonization phenomena to coke quality and yield, environ- mental impacts of foundry coke plant operations, suggested research and development opportunities, and data on components of oven charges and on foundry coke production and shipments.

Jan 1, 1977

By A. C. Wilson

In 1991, local prospector C. ?Mickey? Clement recovered at least three alluvial diamonds from the Michipicoten River. Two of these stones were sent to the Department of Mineralogy, Royal Ontario Museum, where they were identified as industrial grade diamonds with weights of 1.05 and 1.13 carats. Both stones were described as frosted and graphite-inclusion riddled. In 1995, prospector Sandor Surmacz and geologist Marcelle Hauseux discovered diamonds in bedrock approximately 20 km north of the Michipicoten River. An 18.1-kg bulk sample of a xenolith-rich lamprophyre, taken from an outcrop at the side of the Trans Canada Highway north of Wawa, yielded 1 macro diamond and 5 micro diamonds. All but one was gem quality (Sage 2000). Since then, more than 36 occurrences of diamonds in bedrock have been reported in an approximately 30 km2 area centred 20 km north of the town of Wawa. The occurrences are hosted within a sequence of unusual, Archean-aged, heterolithic breccias previously considered to have no economic significance. Ten kimberlite occurrences also have been confirmed in the Michipicoten greenstone belt in the last 5 years. Two of these kimberlites are diamondiferous. To date, expenditures on property acquisition and diamond exploration in the Wawa are estimated at $120 million (CAN). This paper summarizes the geological observations made on these occurrences and discusses including the relationship between the occurrences and the regional geology.

May 1, 2003

By D Reddy Chinnasane

Outline Location of BirchtreeMine and Layout of 124 OB Cut and Fill Mining Background Purpose of the Studies Methodology Results and Analysis Conclusions and Recommendations

Oct 1, 2010

By L. B. Berger

The Haldane gas-analysis apparatus used by the Bureau of Mines is patterned after the device developed by Haldane 4/ and differs from it only in structural modifications that have been added to facilitate operation and simplify construction. The apparatus was developed to permit determination of carbon dioxide, combustible gases, and oxygen with a degree of accuracy not attainable with apparatus of the types ordinarily used for the analysis of fuel gases, flue gases, and similar mixtures. The Haldane apparatus is used by the Bureau of Mines chiefly in the analysis of air samples collected in coal and metal mines and other underground workings and is applied also in the analysis of many other types of gas mixtures when accurate determination of certain constituents is desired.

Jan 1, 1938

By P. J. van der Walt

The paper1(hereinafter BG) by two respected sampling experts contains sound theory and logic that can?t be directly refuted. Nevertheless, a practitioner knows that there is a broader context in which the practice of sampling takes place. This broader context, being less well defined than the theory of correct sampling, receives correspondingly less exposure which this commentary??prompted by? BG?seeks to rectify. ?Correctness? of a sampler is the central concern of BG, where it is presented as a sharp ?black-and-white ?distinction. Accordingly, comments below are grouped under the following headings: ?Correctness in practice ?Without correctness, what can be done? ?The broader context.

Jan 1, 2002

This Bureau of Mines publication contains five papers pertaining to the effective grounding of mine power systems, as follows: Ground-check monitor types and safety characteristics; ground wire monitors for surface coal mines; ground bed design and measurement; electrical ground rod corrosion; and a continuous ground bed resistance monitor.

Jan 1, 1979

By P. Massacci, F. La Marca, G. Bonifazi

Certain deposits of incoherent materials which are near the surface and exploitable by open-pit mining may be characterized in real time before they are mined through an analysis of ground-surface imagery. If the slice to be stripped is not overly thick, in fact, surface texture and color properties may be extrapolated to its entire thickness. Image analysis techniques to process ground surface images acquired in situ(or in the laboratory shortly after their acquisition) which yield pattern vectors representative of RGB color component distributions and HSB texture parameters have been developed. The techniques were applied to a mineral sandy ore deposit containing three different lithotypes. Geostatistical analyses showed that the data used to characterize the lithotypes were reliable. The correct recognition of the lithotypes was carried out using a multi-barycenter classification algorithm. Such in situ image-analysis procedures open the way to the proper selection of the ore to be mined, or the proper way for run of mine (r.o.m).processing, or the appropriate blend to be processed before or at the same time as the mining process itself is enacted.

Jan 1, 1999

By Unknown

More than 60 years ago Lakota (Sioux) Chief Henry Standing Bear asked Korczak Ziolkowski to create a monument of Crazy Horse in the sacred Black Hills. Today, you can see Standing Bear’s dream has grown into enormous reality. Crazy Horse Memorial, mankind’s largest mountain carving in progress, is being carved in the round and when completed will be 641 feet long and 563 feet high. Crazy Horse is only 17 miles from Mount Rushmore National Memorial, giving South Dakota unique boasting rights for having two extraordinary mountain carvings in such close proximity

Jan 1, 2009

This publication summarizes the in-house and contract research and development projects programed for fiscal pear 1980 by the Bureau of Mines under its Minerals Environmental Research activity. The document provides a mechanism for interested parties, including potential contractors, to gain insight into ongoing and projected work of the Bureau's environmental research efforts. Research to identify and correct environmental problems associated with mining and metallurgical operations has long been an integral part of the Bureau's mission. Through the years, efforts of various Bureau programs have yielded valuable information on the origin and control of many of these problems. With the reorganization of the Bureau of Mines in 1979, the Minerals Environmental Technology program was structured to consolidate these efforts into a single program that will systematically investigate al aspects of mining- and processing-related environmental pollution and damage-from initial discovery of the mineral resource to ultimate return of the land to productive use. In fiscal year 1980, the Bureau received an appropriation of about $21 million to conduct research and development work on these problems.

Jan 1, 1980

By Robert L. Frantz

The performances of the three bituminous coal demonstration methane re¬covery boreholes, located in Greene County, Pennsylvania, are reviewed. Development of these vertical holes was largely underwritten by project funds. Reference is also made to an anthracite coal methane project in Luzerne County, Pennsylvania. This involved one vertical hole and was underwritten by a utility company. In addition, an exploratory drilling in the southern anthracite, which provided the project group with coal cores for methane gas analysis, is also cited. The technical and economical data that were gathered from the various methane projects are analyzed. Finally, the advantages and disadvantages of methane recovery by vertical boreholes are assessed.

Jan 1, 1978

By R. L. Marek

The number of persons fatally injured in the California petroleum industry, in 1932 was 24, a decrease of 6, or 20 percent from the number killed in 1931. The decrease in the number of fatalities occurring in 1932 caused the fatality curve of the California petroleum industry to reach its lowest point in 10 years. Changing conditions in the oil industry--reduced personnel, decreased active field development, and curtailed production--have undoubtedly caused a part of this decrease, but continued accident-prevention efforts by the industry have also contributed to the reduction in the number of fatalities for 1932. The Bureau of Mines has analyzed and reported annually the fatalities in the California petroleum industry for a period of 10 years. Figure 1 shows the trend of fatal accidents during that period.

Jan 1, 1933

By Kara A. Teacoach

Current regulations for fire suppression systems in underground coal mines to protect conveyor belt installations have been in place since the Coal Mine Health and Safety Act of 1969 was enacted. Over time, the coal conveyer equipment being used and ventilation conditions underground have changed significantly, particularly the width of the conveyor belts and the use of belt air at the face. The effect of these new conditions on the effectiveness of suppression systems during a fire is not known. The National Institute of Occupational Safety and Health (NIOSH) conducted a study to evaluate the effect of air velocity, water sprinkler activation temperature, and a limited water application time on the effectiveness of water sprinkler fire suppression systems to extinguish large-scale conveyor belt fires. The fire tests were conducted using both new and used 1.8-m-wide, fire-resistant rubber belt that met the Mine Safety and Health Administration (MSHA) flame resistant requirement specified in Title 30, Code of Federal Regulations, part 18, section 18.65 (also known as the 2G test). Tests were conducted using standard response sprinklers with activation temperatures of 68 °C and 141 °C at air velocities of 0.5 and 5.1 m/s. Two tests were conducted at both air velocities for each sprinkler activation temperature, one using a new belt and one with a used belt. The results showed that the suppression system was able to suppress the fires in ten minutes to the point that a miner could extinguish it with a fire hose. However, in several of the tests, the fire reestablished itself a few minutes after the sprinkler water supply was cut off and quickly grew out of control. This report discusses the large scale experimental configuration, the installation specifications of the fire suppression system, and the results and conclusions regarding the effect of air velocity, sprinkler activation temperature, and limited water application on the suppression system performance.

Jan 1, 2010

By W. H. Tomlinson

The fourteenth National First-Aid and Mine Rescue Contest we;; held at the State fairgrounds, Columbus, Ohio, October 2, 3, and 4, 1951. The meet, the first such event in 21 years, was under the auspices of the Bureau of Mines, United States Department of the Interior, and the Joseph A Holmes Safety Association and was sponsored by the National Coal Association, the United Mine Workers of America, and various State mine-inspection departments. The cooperating agencies that contributed to make the meet a success, in addition to the National Coal Association and the United Mine Workers of America, were the Kentucky Department of Mines and Minerals, Ohio Division of Mines, West Virginia Department of Mines, Pennsylvania Department of Mines, and the Columbus Convention Bureau. SUMMARY Fourteen teams from 6 States participated in the mine rescue contest, and 55 teams from 9 States competed in the first-aid contest. Only one of these teams entered as a combination team, that is, participating in both the mine rescue and first-aid contests. The States represented and the number of teams from each State are listed in table 1.

Jan 1, 1953

By H. A. Dakin

"An introduction to the metallurgical requirements of the Flin Flon concentrator reveals the magnitude of ore blending which is required in its operation of three flotation circuits. The resulting variability in flotation heads which has in-creased the separations complexity justified the development of an on-line analysis system.This paper provides a summary of the development and operation of that system. Particular attention is devoted to the problems encountered and where possible their solutions; as the requirements of accurate information and minimum downtime of the sampling system and x-ray analyzer are considered essential. The addition of a recess central computer has provided information in a more easily understood form and as well has allowed the start of automatic reagent control.An indication of the on-line analysis system's value to the concentrators' operation is provided by an examination of the plant in metallurgical data and reagent costs in previous years.The metallurgical plants of Hudson Bay Mining and Smelting lie adjacent to the city of Flin Flon on the Manitoba-Saskatchewan boundary. Plant operations commenced in 1930 treating copper-zinc ore from the local mine. In recent years ore bodies near Flin Flon and in the Snow Lake area, about seventy-five miles east, have been brought into production.By the beginning of 1973 the number of producing mines had increased to nine; with all the ore being handled by the Flin Flon concentrator. Figure l, showing mine ore assays during 1973 indicates the variation in metal content possible."

Jan 1, 1974