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By D. W. Butner

This Information Circular , one of a series published by the Bureau of Mines , reports on the methods and costs of mining and concentrating zinclead ore at the Highland Surprise mine in the Pine Creek area of the Coeur d'Alene region of Idaho . The mine is owned and operated by the Highland Surprise Consolidated Mining Co. , which supervises operations of the Nevada Stewart group of claims , which is adjacent on the northwest . These properties are at the extreme eastern end of a zone of fracturing that strikes northwest across the Pine Creek area . In fractures along this zone are the principal Pine Creek mines ; these are the Highland Surprise , Nevada Stewart , Sidney , Denver , V and Idaho , Liberal King , and Northern Light . Country rock at the Highland Surprise is argillite of the Prichard formation (Belt series ) . Fracturing has permitted the movement of mineral- izing agents that have replaced adjacent walls and crushed country rock with sulfides . Ore minerals are sphalerite and galena with accessory pyrite , chalcopyrite , pyrrhotite , and siderite . Three principal ore shoots were found on the Highland Surprise property . The Highland ore shoot was mined from outcrop to the 400 level . The Surprise ore body has been developed to a depth of 1,400 feet on the dip of the vein . The outcrop of the Surprise ore shoot was 150 feet long and 2 to 4 feet thick ; on the 1,150 ( lowest ) level , the ore shoot is 320 feet long and 10 to 17 feet thick , with good zinc content . Surprise ore shoot No. 2 occurs 250 feet west of No. 1 and has been mined from the 500 to the 1,000 level . From 353,000 tons of ore mined between 1910 and 1948 , the property has a recorded production of 256,000 ounces of silver , 7,500 tons of lead , 24,000 tons of zinc , and 412 tons of copper . Both shrinkage and cut and fill stoping methods are used at the Highland Surprise , but shrinkage is unsuitable for mining below the 700 level , because faulting has weakened the walls . Development of the Surprise ore , as well as exploration laterally and along the strike , is prosecuted steadily . A prospect heading is being pushed westward toward Nevada Stewart ground from the 700 level . The mill has a rated capacity of 275 tons per day and operates near capacity . Selective flotation makes zinc concentrate that is shipped to the Anaconda smelter and lead concentrate that is trucked to the Bunker Hill smelter at Kellogg .

Mar 1, 1950

In presenting this list of permissible explosives and blasting devices, the Bureau of Mines desires to call attention to pages 19 and 24 outlining, the conditions in use under which, and only under which, the explosive or blasting device is permissible. In view of a recent publication recounting trade practice favoring the use of a blasting device without stemming, particular emphasis is placed upon condition 4 on page 19 and condition 2 on page 24. An explosive or a blasting device enumerated in the permissible lists of this Bureau is not permissible in use unless it is properly confined with clay or other incombustible stemming.

Jan 1, 1940

In presenting this list of permissible explosives and blasting devices, the Bureau of Mines desires to call attention to pages 19 and 24 outlining, the conditions in use under which, and only under which, the explosive or blasting device is permissible. In view of a recent publication recounting trade practice favoring the use of a blasting device without stemming, particular emphasis is placed upon condition 4 on page 19 and condition 2 on page 24. An explosive or a blasting device enumerated in the permissible lists of this Bureau is not permissible in use unless it is properly confined with clay or other incombustible stemming.

Jan 1, 1940

By J. G. Donaldson

A bench-scale method for recovering lead and zinc from slimes and mill tailings from the Tri-State District of Missouri, Oklahoma, and Kansas was developed by the Bureau of Mines. Dilute hydrochloric acid, containing sodium chloride, and chlorine gas were used to decompose the mineral constituents. Lead was electrolyzed from the pregnant acid solution, and zinc was precipitated from the depleted electrolyte by neutralization with lime. Up to 98 percent of the lead was recovered in an impure lead electro- deposit assaying approximately 85 percent lead. Zinc recoveries up to 90 percent of the total were attained in a precipitate assaying approximately 40 percent zinc.

Jan 1, 1963

By Gary P. Sames

Shale roof deterioration in coal mines. caused by ventilation air humidity fluctuations, is a common ground control problem. Shale roof deterioration often results in increased accidents, decreased production, inadequate ventilation, and increasing operating costs in maintaining haulage roads and airways. The results of Bureau of Mines research indicate that air tempering entries are an effective method of controlling deterioration prone shales. Some of the conclusions and recommendations drawn from Bureau research include (1) moisture sensitive shales will react adversely to moisture gains and losses, (2) the majority effect of specific humidity fluctuations can be concentrated in and absorbed by tempering entries, (3) tempering entry panels should be located as near to the main intake as possible, (4) tempering panels should be designed for a conservative recovery and provide a minimum of 20-to 30-min air residence time, (5) ventilation and escapeway requirements must be considered early in panel design, and (6) an efficient support and sealant plan can increase the life expectancy of a tempering panel.

Jan 1, 1985

By L. J. Prosser

The Bureau of Mines has completed an underground degasification project in which an underground piping system was used to transport methane from the coalbed to the surface. In a la-month period four horizontal holes were drilled to an average depth of 1,450 feet. All four holes were surveyed vertically and azimuthally. In 991 days of degasification, 255 MMcf of gas was drained from the coalbed. The underground piping system proved to be a safe and effective means of transporting methane from the coalbed to the surface.

Jan 1, 1981

By P. J. Coleman

Research in the field of mining safety and health in the United States plays an important part in protecting the lives of miners. The National Institute for Occupational Safety and Health (NIOSH) Mining Program conducts surveillance, studies and developmental work aimed at improving the safety and health of miners. With recent reviews of the Mining Program by the National Academy of Sciences and the Mining Program response (NIOSH, 2008), the importance of setting goals, conducting high quality engineering and scientific research and evaluating the outputs, outcomes, relevance and impacts of these projects has been reemphasized. Surveillance of reported injuries is a first step in deciding on research directions and in designing specific projects. Groups of injuries often share features and attributes that suggest common causes and may respond to similar preventive efforts. Identifying groups of injuries also serves to prioritize intervention efforts. The Mine Safety and Health Administration (MSHA) Accident and Injury database (MSHA, 2008) provides individual case reports of mining injuries, illnesses and certain no-injury accidents (events such as roof falls that stop mine production or miners? activities for more than one hour). This database is an indispensable resource for researchers and stakeholders needing information on the statistics of these events. From an epidemiological perspective, research projects target groups of miners at risk due to specific patterns of work, equipment, mine settings and the management of safety and health in their mines. Incidence rates are provided by the MSHA data for selected variables, such as surface/underground location, standard industrial classification and state. While incidence rates are the preferred measure for all variables, denominators are not typically available; for example, to more clearly under-stand the data about injury by occupational type, it would be necessary to conduct demographic surveys. A current survey of the demographics of the mining industry should be complete by 2010, which will allow incidence rates to be developed for a number of variables such as age, occupation and experience. This survey will provide the first update of its kind since the first survey was conducted in 1985.

Jan 1, 2010

By S. P. Sandoval

Several researchers have shown that the surface of chalcopyrite becomes hydrophobic under oxidizing conditions. Because dissolution of copper from chalcopyrite in dump leaching occurs under oxidizing conditions, the U.S. Bureau of Mines studied the effect of surfactants on chalcopyrite leaching under dump chemical conditions. Surfactants were selected for study because they can lower interfacial tension. The tests were conducted in shaking water baths using 250-mL Erlenmeyer flasks in statistical experimental design formats. The addition of nonionic surfactants increased copper extraction in the fernc sulfate leaching of chalcopyrite when sufficient Fe3+ was present. A positive interaction between Fe3l+ concentration and surfactant concentration was demonstrated. Copper concentration in the leachhing solutions was increased by as much as 100 pct at 25° and 50° C by adding nonionic surfactants. ionic surfactants decreased leaching. The structure of the nonionic surfactants and their hydrophile-lipophile balance (HLB) influenced surfactant performance. The branched hydrophile of an ethoxypolyol was beneficial to surfactant performance. The ethoxypolyol was the superior surfactant at 25° C, but became unstable at 50° C. Four surfactants, an ethoxyalchohol and three block copolymers, performed best at 50° C.

Jan 1, 1990

By Cheryl Hill, Michael Keane, Pamela Mike, Raghoottma Pandurangi, William Wallace, Mohindar Seebra, Val Vallyathan

"Dipalmitoyl glycerophosphorylcholine (lecithin) dispersed in physiologic saline, a model of the primary component of pulmonary surfactant, is adsorbed by respirable quartz and aluminosilicate dusts. Dust cytotoxicity as measured by erythrocyte bemolysis and pulmonary macrophage enzyme release is suppressed by this adsorption. The degree of suppression of hemolytic potential versus specific adsorption of lecithin from dispersion in saline by respirable quartz and kaolin dusts are compared with dusts' BET specific surface areas to interpret the prophylactic effect of lecithin adsorption. Dust hemolytic potential versus medium pH is presented. Fourier transform infrared spectroscopy and photo-acoustic spectroscopy of lecithin on quartz and of lecithin on kaolin are presented and reviewed with results of studies of the time course of removal of lecithin adsorbed on mineral surfaces by digestion by phospholipase enzyme. Results are discussed in terms of a model of prompt neutralization of respired mineral dusts by pulmonary surfactant, and a gradual re-toxification by digestive processes acting on the adsorbed prophylactic surfactant coating following phagocytosis. INTRODUCTIONQuartz dust of respirable size is well known to cause fibrotic lung disease, but numerous questions persist in the understanding of the initiation and progression of this disease. Our approach concentrates on physical and chemical aspects of mineral dusts early-on in their interactions with living organisms, and we have chosen simplified models to investigate that interaction.In the alveolar ·spaces of the lung, tissue is coated with a surface-active material (pulmonary surfactant), which, among other functions, mechanically stabilizes the lung from collapse by reducing the surface tension of water in the alveolar sacs.1 This surfactant is also the material that is first contacted by a mineral particle that is transported to an alveolus and is impacted there. This surfactant material has been studied extensively. The primary components are known to be proteins (about 11 % in dog lavage fluid), and phospholipids (about 88%).2 Pbosphatidyl cholines constitute roughly 80% of the phospholipid fraction; about 70% of the phosphatidyl choline fraction is dipalmitoyl lecithin (DPL).2 Respirable aluminosilicate particles are capable of adsorbing dipalmitoyl lecithin from dispersion in physiologic saline, a model for a possible initial event occurring upon deposition of a particle in a pulmonary alveolus. As may be seen from Figure 1, the DPL molecule has several fixed charges at neutral pH; a positive charge on the trimethylamine (choline) moiety, and a negative charge on the phosphate group. Also evident are the two fatty acid residues of palmitic acid, which are bonded through ester likages to the glycerol segment of the molecule. The fatty acid moieties of phosphatidyl choline make the molecule inso1uble in aqueous solutions under normal conditions, but a colloidal unit of aggregated molecules called a micelle is usually formed spontaneously above a certain minimum concentration. Small micellar vesicles are generally formed in the laboratory by using ultrasonic agitation or by solvent evaporation methods."

Jan 1, 1990

By V. E. Erwin, W. W. Adams

"Production of explosives for industrial use in,the United States during 1934 continued the upward trend begun in 1933 from the low-level output of 1932, and the output in 1934 was only slightly less than in 1931.Reports to the United Stated Bureau of Mines from companies engaged in the manufacture of industrial explosives showed that the quantity of explosives manufactured in the United States and sold during 1934 for use within the various States was 314,767,922 pounds - 23 percent more than in 1931.Production during 1934 included 39,207,845 pounds of permissible explosives 5 206,625,027 pounds of high explosives other than permissibles, and,68,935,050 pounds of black blasting powder of which 37,192,700 pounds were in granular form and 31,742,350 pounds in pellet form. These figures represent an increase over 1933 of 15.6 percent for permissible explosives, 30.9 percent for other high explosive, and 7.4 percent for black powder.Coal-mining operations were the chief consumers of permissible explosives; 99 percent of the total output in 1934 was used, in coal mines. The proportion used by bituminous mines was 59 percent and by anthracite mines 40 percent. Coal mining was likewise the principal consumer of black blasting powder, taking 88 percent of the total sales during 1934; of this proportion, bituminous mines received 78 percent and anthracite mines between 9 and 10 percent. Consumers of high explosives other than permissibles were more varied; the reports showed that 11 percent of the total quantity sold was for coal mining, 22 percent for metal mining, 17 percent for quarrying and nonmetallic-mineral mining, 46 percent for railway and other construction work, and 4 percent for all other purposes."

Oct 1, 1935

By Wilbert J. Huff

For the past 9 years , the technical studies conducted by the Explosives Division of this Bureau have been summarized in a series of reports issued annually . The following account presents investigations undertaken from July 1 , 1943 , to June 30 , 1944. The work is detailed under a number of main headings corresponding to the organizational structure of the Division , the various activities being under the immediate direction of unit chiefs , who report directly to the author . Specific credit , however , is due to the individual unit leader and his assistants .

Jan 1, 1945

By James Westfield

Uranium activity has introduced a comparatively new hazard to United States mining. In addition to the hazards common to all mines, uranium mines have a complex health problem of radiation damage. Like many new processes, radiation and nuclear energy can be made to serve man in many useful ways when properly understood and handled; but, like fire, gases, and electricity, their potential dangers must be known and respected, and appropriate precautions must be taken or death may result. Since 1950 the Public Health Service has been conducting basic investigations on exposure to radon and its daughter products and the effect of exposure upon the health of miners in uranium mines of the Western States. The Bureau of Mines assisted in several of these investigations, especially in mines on Indian lands. The studies have shown that a serious health hazard exists from radioactive exposure that might cause lung cancer if continued over a number of years. The Public Health Service report, Control of Radon and Daughters in Uranium Mines and Calculations on Biologic Effects,6/ shows that 55 percent of the uranium mines employing 64 percent of the miners had atmospheric concentrations more than five times the working level now accepted as reasonably safe for industrial exposures. Extensive control measures are necessary to reduce these concentrations to the suggested working level of less than 300 micromicrocuries of total radon daughter products per liter of air.

Jan 1, 1958

By Douglas F. Scott

This case study provides an example of how social marketing was applied to meet the needs of business customers. Federal regulations require that all companies develop a written program to track hazardous chemicals at their sites. The HazCom Writer, created by the National Institute for Occupational Safety and Health (NIOSH), is a software tool designed to help companies prepare their required Hazard Communications (HazCom) written plan and list all hazardous chemicals at the company's worksite. The social marketing goal was to provide a product for small- to medium-sized companies to use for federal HazCom rule compliance. The HazCom Wm'ter is a direct NIOSH response to customer and stakeholder needs (including the Mine Safety and Health Administration, the mining community, and Occupational Safety and Health Administration- regulated companies).

Jan 1, 2009

By John R. Hoskins

Uniaxial compressive strength of rock is usually determined in the laboratory from cylindrical samples that vary in diameter from 5/8 to 8 inches, using a spherically seated compression head of unspecified size. The Bureau of Mines conducted a series of tests on limestone, marble, sand-stone, granite, and plaster of paris to determine the influence of the spherical head sizes and the specimen diameters themselves on the uniaxial compressive strength. Cylindrical samples of several different diameters of each rock type, all having a length of twice their diameter, were prepared and broken using at least three different diameter spherical heads. Analysis of the data shows that spherical head size does not significantly affect the uniaxial compressive strength of cylindrical rock samples. However, the diameter of the rock specimens does significantly affect the uniaxial compressive strength. Within the range of specimen diameters tested, a coefficient of variation of 6.4 percent for plaster of paris can be attributed to the selection of specimen diameter alone. Similarly, a maximum coefficient of variation of 4.7 percent for the rock types tested can be attributed to the specimen diameter alone.

Jan 1, 1969

By Irving Hartmann

When permissible explosives are used in coal mines according to the procedure recommended by the Bureau of Mines they are relatively safe, and no mine explosions are known to have resulted from this type of blasting. However, unsafe blasting practices - the use of nonpermissible explosives or the improper use of permissible explosives - have caused many serious disasters. In fact, such unsafe practices constitute the third most important cause (exceeded only by electricity and the use of open lights and smoking) of coal-mine explosions in the United States. During 1929-1947, inclusive, 81 explosions, resulting in 475 fatalities, were ascribed to unsafe blasting. The hazards of black powder, dynamite, and other nonpermissible explosives in coal mines have been recognized for many years, and attention has been called to this in numerous Bureau of Mines publications. Not only can these explosives ignite namable gas-air mixtures readily, but they can also ignite coal dust, as has been illustrated repeatedly in tests and at educational public demonstrations at Bruceton and elsewhere.

Jan 1, 1952

By B. S. Covino

The Bureau of Mines, U.S. Department of the Interior, is conducting research to devise substitute corrosion-resistant materials by using ion implantation to form alloyed regions near the surfaces of metals. These alloys were prepared by implanting 25-kev Cr+ and/or Ni+ ions into iron. Their resistance to corrosive attack was evaluated by determining their anodic polarization behavior under potentiodynamic conditions in a solution containing sodium chloride, boric acid, and sodium borate. These electrochemical studies have shown that the general corrosion resistance of ion-implanted alloys was comparable to nominally equivalent bulk alloys. The pitting-corrosion resistance of the ion-implanted alloys was superior to that of iron, although not as good as that of most of the bulk alloys tested.

Jan 1, 1980

Oil from shales has long been a source of fuel in foreign countries; however, in the fuel economy of the United States this source is classed as a reserve for future needs. In fad, shale oil has never been produced here in quantities necessary to establish oil-shale utilization as a sustained industry. The first known resources of stored energy that man endeavored to utilize were probably wood and water, and from these he directly obtained heat and power, respectively. With the evolution of man came the search for and the development and use of other natural fuel resources, the series progressing through the solid, liquid, and gaseous fuels until today those of one type can be converted into another, depending upon the use for which they are intended. The most important fuels are those that appear naturally in the most concentrated, conveniently obtainable, and usable forms. With the discovery of each new and more concentrated fuel there has been an appreciable increase in the importance of and number of devices for converting these fuels into energy.

Jan 1, 1938

By R. G. Dressler

The Federal Bureau of Mines designed, constructed, and operated a demonstration plant at Louisiana, Mo., to produce gasoline, liquid fuels, and organic compounds from coal by a modified Fischer-Tropsch gas-synthesis process. Satisfactory equipment was developed to produce and purify synthesis gas and convert it into the desired products. Coal or coke was gasified with oxygen and steam to make a gas consisting essentially of carbon monoxide, hydrogen, and carbon dioxide. Dust in the raw gas was removed by cyclone separation, water scrubbing, and electrostatic precipitation. Carbon dioxide, hydrogen sulfide, and organic sulfur were removed with diethanolamine, iron oxide, and activated carbon. The gas was passed over iron catalyst and was converted into synthetic liquids, which were then separated and fractionated into gasoline, diesel oil, other liquid fuels, and oxygenated organic compounds. A 39-day continuous run demonstrated the feasibility of the process. Addition of 3 milliliters of tetraethylead per gallon of upgraded (or finished) gasoline gave a product with an octane rating up to 90 by the research method. After a caustic wash, the diesel oil was of a superior quality; its cetane number was 60 or above.

Jan 1, 1961

By A. V. Hooker, E. J. Coggeshall

"The Bureau of Mines for some time advocated the firing of all blasts in coal mines as single shots, and this method of firing is the general practice in American bituminous-coal mines. All single shots can be fired with permissible single-shot units so designed that they will not ignite mixtures of methane and air.If several shots in a face are fired singly it is necessary to return the face after each shot. In some mines having steeply pitching coal seams, this may be dangerous or even impossible, under these conditions shots are usually fired simultaneously.Several shots cannot be fixed simultaneously with permissible single-shot blasting units, and safe types of multiple shots blasters are not readily available. This means that the firing of multiple shots in gassy mines is usually accompanied by the possibility of gas ignition as the blast occurs.Tests have been made at the Pittsburgh Experiment Station to determine the possibility of developing safe types of multiple-shot units suitable for such use, or of applying other type safely in gassy sections of mines where firing shots singly is impracticable.The tests may be divided into the following four groups:1. Tests to demonstrate hazard in the use of existing types of multiple-shot units of the portable generator type.2. Tests to show the electrical characteristics of multiple-shot generator units relative to the possibility of preventing igniting sparks and of modifying the design and application of such units in furthering safety."

Mar 1, 1935

By D. S. Kingery, F. F. Kopsch

The practice of using two or more main ventilating fans is common at large coal mines throughout the coal-mining industry. To assure adequate and efficient ventilation at may mines, such multiple-fan systems are necessary. The hazards associated with interrelated ventilating currents if a fan fails are controversial, and to date little effort has been made to study this specific problem and to determine corrective measures. The obvious questions are: 1. Is there a hazard? 2. Under what circumtances does it exist? 3. How serious is it? 4. What are corrective measures? Most members of the mining fraternity agree that reduced quantities of air and changed airflow patterns introduce potential hazards, especially where gaseous conditions exist when mechanized methods are used in concentrated mining 0 The seriousness of the hazard depends on the ease with which methane accumlates in face areas or haulage roads, the quantity of methane in workedout areas, and the extent to which reversed air currents interfere with escape and recovery operations after mine fires or explosions. These studies cover three mines and give the distribution of air for the specific conditions show. Each mine probably has somewhat different airflowpressure relationships between fans. This depends on the number of fans, the

Jun 1, 1959