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By F. M. Goodwin, John Campbell, G. W. Jones

"INTRODUCTION The investigation of the general hazards of combustible gases and vapors in manholes owned by the Edison Electric Illuminating Co. and the study of methods for eliminating these hazards, conducted by the Bureau of Mines, the Edison Electric Illuminating Co. of Boston, and the Boston Consolidated Gas Co. since 1929, was continued during 1933.From May and through December 1933 these tests were supplemented by a study of the manholes of the New England Telephone & Telegraph Co. The test crew was under the direct supervision of John Campbell, superintendent of the Special Service Department of the Edison Electric Illuminating Co., and F. M. Goodwin, vice president of the Boston Consol¬idated Gas Co.The procedure of sampling manhole atmospheres and of shipping the samples to Pittsburgh was the same as that used heretofore. In previous reports the relative explosibility of the samples was calculated by adding the percentages of the illuminants, hydrogen, carbon monoxide, methane, and ethane, dividing the total by 6.5, and multiplying by 100. Experience has shown that the factor 6.0 is more nearly correct; therefore, this has been used in calculating the relative explosibility of all the samples listed in appendix A and B of this report. If gasoline vapor is present a smaller factor must be used.ACKNOWLEDGMENTSThe cooperative investigation was arranged through the interest and effort of W. C. Bayliss, president of the Edison Electric Illuminating Co. of Boston; W. C. Beckjord, vice president and general manager of the Boston Consolidated Gas Co., and A. C. Fieldner, chief engineer, Experiment Stations Division, United States Bureau of Mines. Thomas H. Haines, superintendent, Distribution Department of the Edison Electric Illuminating Co., cooperated heartily in furnishing both men and information for the work."

Oct 1, 1934

By Richard L. Sayrs

"The Stiner zinc prospect near the north boundary of Union Tennessee, and the Bunch Hollow property 5 miles northeast in Claiborne County, Tennessee, were diamond-drilled by the Bureau of Mines during the period .September 1, 1944, to February 22, 1945. Seventeen holes totaling 5,687 feet were completed, 13 of which, totaling, 5.083 feet, were on the Stiner property and the remainder, totaling 604 feet, at Bunch Hollow.The Stiner prospect is about 1 mile east of the old workings known as ""New Prospect"" or ""Lead Mine Bend."" The Federal Geological Survey made a study' of the area early in 1944. The prospect was first visited in August 1944 by Bureau of' Mines engineers3/ accompanied by members of the Federal Geological Survey.4/ The locality is reached by traveling State Road 33 north-about 9 miles from Maynardsville, Tenn., thence northwest about 7 miles by an improved county road that leads to the mine (fig. 1). The tract comprises an area of about 181 acres held by G. S. Stiner of Sharps Chapel, Tenn.; it is now under option to the Universal-Exploration Co. of Jefferson City, Tenn.The Bunch Hollow property, about 5 miles northeast of the Stiller prospect, was also studied by the Federal Geological Survey previous to being;Visited by Bureau of Mines engineers in August 1944. It is reached by traveling north from Maynardsville, Tenn., on State Road 33 about 13 miles, thence northwest by county road 6 miles to the property (fig. 1). The last 3 miles of the county road are in poor repair but are passable during the entire year. The property comprises an area of approximately 300 acres and is held by the imperial Mining Co., Pressman's Home, Tenn.Few reliable data are available as to the history of the Stiner prospects themselves. However, the New Prospect mine, 1 mile west, has had a colorful past, This mine was opened in 1883 and was worked intermittently until 1918, by which time more than 65,000 tons of concentrates had been shipped. No further work was done until 1942, when the mine pillars were robbed and 1,900 tons of ore averaging 25 percent zinc was shipped to the New Jersey Zinc Co., Austinville, Va."

Apr 1, 1946

By Deborah A. Kramer

An economic and technical evaluation of a proposed process to recover alumina by leaching calcined kaolinitic clay with sulfurous acid is presented in this Bureau of Mines report. After the insoluble portion of the clay has been removed by leaching, monobasic aluminum sulfite is precipitated from the pregnant leach solution by partial hydrothermal decomposition. Further heating completes the decomposition to an impure alumina hydrate. This intermediate is purified in a modified Bayer process, which includes dissolving the alumina hydrate in a caustic solution at high temperature and pressure, then decreasing the temperature and pressure to precipitate alumina trihydrate. Calcining the trihydrate produces the alumina product. A cost estimate was prepared for a plant producing 1,000 tons of alumina per day, 350 d/yr. The estimated operating cost is approximately $475 per ton of alumina. This is substantially higher than a comparable estimated operating cost for the Bayer process of $250 per ton of alumina. The proposed process does not appear economically attractive, even as a method to modify a current Bayer processing plant to use a kaolinitic clay feed. High capital costs and high energy requirements make the process prohibitively expensive.

Jan 1, 1983

By S. H. Ash

A CLAY, sand, and gravel deposit known as the "buried valley" of the Susquehanna River is situated in the Northern field of the anthracite region of Pennsylvania near Wilkes-Barre. The presence of this buried valley and the uncertainty regarding the extent and physical condition of the water-bearing valley-fill deposits have made great care necessary in mining operations to avoid breaking the strata between the mine workings and the valley-fill deposits to the extent that inundation of the mine workings would follow. The principal factor that threatens to cut short the life of the anthracite industry, to curtail production, and to affect the economic structure of the people and business dependent on anthracite for their livelihood is inundation of anthracite mines (6,7).3

Jan 1, 1950

By Robert R. Stein

Using an automated drill test fooure, the U.S. Bureau of Mines measured the sound power levels produced by a small, pneumatic, rotary roof drill. A series of tests was conducted to determine (1) the relative effectiveness of several drill muffling schemes and (2) the relationship between drill sound power and pneumatic power supplied to the drill. The influence of rotation rate (i.e., airflow) and feed thrust on the penetration rate of the drill was also noted.

Jan 1, 1989

By Kenneth G. Broadhead

The objective of this rare-earth oxalate study by the Bureau of Mines was to determine systematically by radiochemical techniques what effects, if any, could be attributed to the several variables--temperature, digestion time, acid concentration, rare-earth concentration, oxalic acid concentration, stirring, and the presence of other rare-earth ions. A Latin Square experimental design was used to evaluate statistically some of the variables. Precipitation losses ranged from near zero to about 7 percent, and mineral acid and rare-earth concentration were the predominant factors affecting completeness of precipitation. Quantitative oxalate precipitation of the rare-earth elements was achieved by controlling the experimental conditions as follows: (1) Maintaining rare-earth concentrations above 0.01M; (2) stirring the mixture several minutes after precipitation; (3) using an adequate (two to five-fold) excess of oxalic acid; (4) precipitating at room or iced temperature and digesting for at least 1 hour; (5) avoiding an excess of mineral acid and, if possible, maintaining the pH above 2.0; and (6) avoiding excess complexing agents such as EDTA (ethylenediaminetetraacetic acid). In the past 20 years research aimed at developing more efficient separation and purification techniques applicable to the rare-earth elements and yttrium has been extensive. Common to most of these procedures has been the use of oxalic acid to precipitate this group of elements selectively. However, this particular use of oxalic acid has a much earlier origin; its application in precipitating yttrium was first reported by Mosander (8)4 in 1843. Despite long and popular employment of this technique, only limited and somewhat conflicting data are available regarding the many factors affecting the degree of rare-earth oxalate precipitations.

Jan 1, 1961

By F. J. Perzak

The Bureau of Mines conducted a study to develop a standard fire test for 5-gal containers used for storing combustible fluids in underground coal mines. A standard test method was developed which evaluates the performance of the container in a 4-min tray fire. Bureau investigators used the standard test method to evaluate several types of closed 5-gal plastic and metal cans in outdoor tests. Each can tested contained 1 gal of nonfire-resistant (NFR) hydraulic oil. A container failed the test if it lost its contents in any of seven trials. Contents spilled either as a result of thermal rupture or melting. Fewer than 10 pct of the metal containers failed this criterion, but all the plastic containers failed. The metal container failures were usual-ly due to tipping over during pressure relief, which spilled the NFR oil. Replacing the NFR oil in the container with kerosene resulted in failure of more than 30 pct of the metal containers. The standard tests and preliminary tests showed that plastic containers are not equivalent to metal containers in their ability to contain combustibles such as lubricants and greases in a fire. For solvents and lubricants more volatile than NFR hydraulic oil, approved metal safety containers are recommended.

Jan 1, 1985

By Michael J. Friedel

The integrity of mine structures, such as the roofs, ribs, face and supporting pillars, is difficult to assess beyond the exposed surface. To mitigate potential rockfall hazards, the U.S. Bureau of Mines is assessing the usefulness of Rayleigh wave dispersion analysis to detect damage and stress-relieved zones in mine structures. Classical surface wave dispersion modeling is utilized at both laboratory and field scales in damaged and undamaged material to assess the integrity of a mine pillar and roof. To more fully exploit Rayleigh wave propagation characteristics, derivation of a novel dispersion parameter was conducted using a convolutional model. The development of a suitable Rayleigh wave dispersion system based on insight derived from forward modeling is presented. The application of inverse modeling for damage and stress assessment in the mine environment is also discussed.

Jan 1, 2010

By A. R. Mumford

During the course of an investigation conducted by the fuel section of the Bureau of Mines , on a hand- fired return- tubular boiler plant , it was found that the average cost of fuel to produce 1,000 lb. of steam was $ 0.5287 . Tests conducted after some simple changes had been made in the furnaces , and in the control of the boilers , showed the previous high cost of fuel per 1,000 lb. of steam could be reduced to the reasonable figure of $0.3540 , or the equivalent of over 30 per cent saving in fuel cost .

Mar 1, 1923

By Paul M. Tyler

Calcium chloride is a conspicuous example of a former waste product that has found a place for itself in the onward march of civilization. Formerly considered a troublesome constituent of the effluent sewage of many chemical manufacturing plants and salt works, it has now become a commercial product of substantial importance, with sales aggregating almost six million dollars in 1929. The point has not yet been reached where it would seem profitable to undertake large-scale production of calcium chloride as a main product, but as a byproduct it has become an item that warrants serious consideration by all who are in a position to recover it at sufficiently low cost. The largely increased demand for bromine and for certain magnesium salts, which are likewise potential byproducts associated with calcium chloride in most salt-works bitterns (and brines generally), adds further impetus to commercial research directed toward the fuller utilization of the natural saline resources of the United States.

Jan 1, 1934

By Joseph J. Wallace

1. The investigation shows that there are two coal beds of major importance in Perry County from the standpoint of present production -Flag and Fire Clay -and two beds of minor importance -Haddix and Hindman. The Flag and Fire Clay beds contain the largest remaining known reserves. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 tons per acre-foot of coal in place, are estimated at 840 million short tons as of January 1, 1954. Of this total, 720 million short tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics are too meager for making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, these should be added to the total estimated reserves.

Jan 1, 1954

Consumption and intensity of use trends for twelve metals, by industrial end use, were estimated for 1972 through 198Z. The trends were then forecast through 1993 using standard statistical methods. The intensity of use measure selected is the quantity of metal consumed per constant dollar output of a specific industrial sector. The metals studied were aluminum, chromium, cobalt, copper, lead, manganese, nickel, the platinum-group metals, tin, titanium, tungsten, and zinc. Average annual growth rates for the following four of the twelve metal increased from 1972-82 as follows: aluminum, 1.00 percent; platinum-group metals (consisting of platinum, palladium, and iridium), 8.83 percent; titanium, 7.82 percent; and tungsten, 6.09 percent. Consumption. for the remaining eight metals decreased at average annual rates ranging from 0.58 percent (copper) to 5.37 percent (manganese).

Jan 1, 1986

By F. D. Everett

The Burgin shaft of Bear Creek Mining Co. near Eureka, Utah, was sunk during 1956 and 1957 as part of an exploratory program, searching for lead, zinc, copper, silver, and gold ore bodies hidden from the surface by several hundred feet of volcanic rocks. This paper describes the sinking methods and operating practices of Centennial Development Co., contracting firm for Bear Creek Mining Co., in sinking a 3-compartment vertical shaft 1,100 feet. The operation featured the Cryderman positive-action, clam-type shaft mucker. The shaft was completed in 142 days by a shaft crew of 10 men and a top force of 10 men, including supervision.

Jan 1, 1959

By Dennis R. Kasper

This study evaluates selective environmental impacts of two distinct in situ mining techniques. In situ leaching of uranium, porphyry copper and native copper and in situ borehole (slurry) mining of uranium, sandstone, and pebble phosphate ores are the techniques and minerals investigated. The potential impacts onsite in the desert southwest (porphyry copper), Michigan (native copper), Texas and Wyoming (uranium), and Florida and North Carolina (phosphate) are addressed and discussed. The study emphasizes those impacts which are unique to in situ solution leaching and borehole slurry mining. Impacts which are characteristic of all construction projects in the general geographical areas investigated, such as socioeconomic effects on surrounding communities and site-specific impacts, such as rare and endangered species, are beyond the scope of this study. For each of the in situ processes and associated ores investigated, the physical and chemical characteristics of the systems are described, the toxicity of the leaching solutions are presented, and the potential impacts on the environment are developed.

Jan 1, 1979

By D. R. Tesarik

As part of its research program to investigate ways of improving resource recovery and reducing subsidence, researchers from the U.S. Bureau of Mines placed instruments in the B-North ore body of the Cannon Mine, Wenatchee, WA, to monitor cemented backfill and rock deformation during mining. The vibrating-wire gauges proved to be reliable and versatile, and approximately half of the instruments are providing data after 2 years of use. A two-dimensional, finite-element model was used to analyze the Cannon Mine's multilevel bench cut-and-fill mining method and predict rock and backfill displacements. The model accurately predicted rock displacements, but the predicted and measured displacements in cemented backfill had a correlation coefficient near zero, indicating that the model should only be used to predict rock displacements and not backfill displacements. A finite-difference model was also used to evaluate the stability of a cemented backfill pillar. Results can be used to conservatively predict backfill stresses, but on-site observation of pillar failures coupled with in situ measurements are needed to make more accurate predictions. An ongoing evaluation of the mining system has indicated that filling the primary stopes tight to the back with cemented backfill allowed these pillars to carry overburden loads soon after the cemented backfill was placed.

Jan 1, 2010

By D. Harrington, W. J. Fene

That fatalities from mine explosions can be very much reduced from the experience of past years if not wholly eliminated was fairly well demonstrated during the fiscal year ended June 30 , 1934 , there being only 28 deaths in the United States from explosions during this period . This is by far the lowest number of fatalities from explosions in the history of coal mining in the United States insofar as records are available . Although the frequency of occurrence of explosions has not decreased greatly during the past 6 years , there has been a marked decrease in severity , indicating that our coal -mining people are taking more effective precautions to prevent the spread of explosions . Pennsylvania is a good example of what may be done in reducing both the frequency and the severity of explosions ; by the adoption of up- to - date safety measures , Pennsylvania bituminous mines now have the enviable record of only one major explosion disaster in more than 5 years , and the one major explosion which did occur cost but 7 lives although 277 persons were exposed ; their lives were saved because rock- dusting prevented the spread of the flame and violence . Many of our other mining States are making definite progress in working mines without disastrous explosions and fires ; some of these , like Alabama , West Virginia , Indiana , Wyoming, and others now operating with few , if any , explosions , have had anything but a favorable record in the past .

Jan 1, 1935

By J. P. Morris

A diphenyl ether calorimeter for measuring high-temperature heat contents of ferrous alloys and iron-and steelmaking slags was constructed and calibrated with specimens of molybdenum, alumina, and platinum that were heated to temperatures ranging from 1,720° to 1,875° K. The standard deviation of the calibration measurements was 0.37 percent. By measurements of the enthalpy of delta and liquid iron, the heat of fusion of iron was found to be 3,298 ±100 cal per mole.

Jan 1, 1966

By Howard P. Hamlin, John W. Sweeney

Shales , clays , and loess in Iowa were tested and evaluated to determine feasibility of producing lightweight aggregate by commercial rotary - kiln or sintering methods . Preliminary testing was conducted in a muffle furnace . Rotary - kiln tests were conducted in a 16 - inch by 14 - foot rotary kiln . Concrete cylinders and cubes were tested to determine qualities of the aggregate . Three samples made suitable lightweight aggregate by rotary - kiln methods and two by sintering .

Jan 1, 1964

By E. C. Fitch

This report discusses fire-resistant hydraulic fluid safety from three different directions. First, results of a survey prepared for the Fire Resistant Hydraulics Journal by the staff of the Fluid Power Research Center are analyzed. Second, operational limitations of fire-resistant hydraulic fluids are examined. Finally, laws and standards of various foreign countries are investigated. Three conclusions are derived from a close study of fire-resistant hydraulic fluid safety from these three directions. First, a significant number of experts in the fluid power industry are no in agreement about aspects of fire-resistant hydraulic fluid fire-resistance and toxicity. This indicates a need for more in depth research. Second, the use of fire-resistant hydraulic fluids involves a compromise between the decreased fire hazards and increased toxicity and machine incompatibility problems. Finlly, major foreign governmental agencies have thorough laws and standards concerning fire-resistant hydraulic fluids. These laws and standards may provide a solid framework for further international research into fire-resistant hydraulic fluid safety.

Jan 1, 1979

These tentative inspection standards have been prepared as a guide for the Federal inspection of the anthracite mines of the United States. The Federal Coal Mine Inspection Division is not a mining-law-enforcement

Jan 1, 1943