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Elemental composition of airborne particulates in uranium mining and milling operations

Description: Airborne particulates were collected through filters in occupational areas of the uranium mining and milling complex located in Pocos de Caldas, Brazil. The filters were analyzed by microPIXE (particle induced x-ray emission) combined with Rutherford Backscattering (RBS) of the incident protons. The results are discussed in the paper. 4 references, 6 figures, 1 table.
Date: January 1, 1984
Creator: Paschoa, A.S.; Wrenn, M.E.; Jones, K.W.; Cholewa, M. & Carvalho, S.M.
Partner: UNT Libraries Government Documents Department

Manganese Availability - Market Economy Countries: A Minerals Availability Program Appraisal

Description: Report issued by the U.S. Bureau of Mines discussing the worldwide availability of manganese. As stated in the introduction, "the purpose of this report is to evaluate selected domestic and market economy country resources of manganese for metallurgical application. Individual mine and deposit evaluations were performed on the basis of tonnage, grade, and cost of production" (p. 2). This report includes tables, illustrations, and a map.
Date: 1984
Creator: Coffman, Joseph S. & Palencia, Cesar M.
Partner: UNT Libraries Government Documents Department

US uranium mining industry: background information on economics and emissions

Description: A review of the US uranium mining industry has revealed a generally depressed industry situation. The 1982 U/sub 3/O/sub 8/ production from both open-pit and underground mines declined to 3800 and 6300 tons respectively with the underground portion representing 46% of total production. US exploration and development has continued downward in 1982. Employment in the mining and milling sectors has dropped 31% and 17% respectively in 1982. Representative forecasts were developed for reactor fuel demand and U/sub 3/O/sub 8/ production for the years 1983 and 1990. Reactor fuel demand is estimated to increase from 15,900 tons to 21,300 tons U/sub 3/O/sub 8/ respectively. U/sub 3/O/sub 8/ production, however, is estimated to decrease from 10,600 tons to 9600 tons respectively. A field examination was conducted of 29 selected underground uranium mines that represent 84% of the 1982 underground production. Data was gathered regarding population, land ownership and private property valuation. An analysis of the increased cost to production resulting from the installation of 20-meter high exhaust borehole vent stacks was conducted. An assessment was made of the current and future /sup 222/Rn emission levels for a group of 27 uranium mines. It is shown that /sup 222/Rn emission rates are increasing from 10 individual operating mines through 1990 by 1.2 to 3.8 times. But for the group of 27 mines as a whole, a reduction of total /sup 222/Rn emissions is predicted due to 17 of the mines being shutdown and sealed. The estimated total /sup 222/Rn emission rate for this group of mines will be 105 Ci/yr by year end 1983 or 70% of the 1978-79 measured rate and 124 Ci/yr by year end 1990 or 83% of the 1978-79 measured rate.
Date: March 1, 1984
Creator: Bruno, G.A.; Dirks, J.A.; Jackson, P.O. & Young, J.K.
Partner: UNT Libraries Government Documents Department

SOUDAN 2 nuclear decay experiment. Progress report

Description: Construction of the experiment cavern on the 27th level of the SOUDAN iron mine in northern Minnesota began early this year and will be complete early in 1985. The first 1200 tons of the detector itself is also under construction in the US and UK; installation will begin in mid 1985. Physics exploitation will begin early in 1986 and the first 1200 ton module will be complete early in 1987. The detector may be expanded to between 3 and 5 such modules in the cavern. The detector is an iron tracking calorimeter (rho = 2) consisting of stacks of corrugated steel sheets each 1.2 mm thick. The corrugations form hexagonal channels 1 m long and 16 mm in diameter. A uniform electric field along these channels is provided by the voltage grading arising from the constant standing current in the Hytrel tubes (rho = 2 x 10/sup 12/ ..cap omega.. cm) that line each channel. The tubes are insulated from the steel by sheets of mylar. Ionization in the gas in the tubes drifts in the uniform field to the end of the tube where it is amplified linearly and detected by a matrix of anode wires and cathode strips. The electronics registers both the drift time and the pulse height of all signals.
Date: June 29, 1984
Creator: Minnesota; Argonne; Oxford; Rutherford & Collaboration, Tufts
Partner: UNT Libraries Government Documents Department

U-bearing particles in miners' and millers' lungs

Description: The size distribution of uranium-bearing particles in air particulates in occupational areas of active uranium mines and mills is largely uninvestigated. Investigation of the size of residual uranium-bearing particles in uranium miners' and millers' lungs is warranted because significant inhalation of uranium can occur in certain occupational areas. Average uranium concentrations of about 0.3 ppM U in uranium miners' and millers' lungs have been reported. Local uranium concentrations in uranium-bearing particles inhaled and regionally deposited in the lungs of uranium miners and millers are orders of magnitude larger than the average uranium concentrations reported. The feasibility of using microPIXE (particle induced x-ray emission) techniques to search for such uranium-bearing particles embedded in lung tissues has been demonstrated. Proton microbeams 20 ..mu..m in diameter, scanning in 5 ..mu..m steps, were used to irradiate sections of lung tissues 10 to 40 ..mu..m thick. The paper will briefly describe the method, and present and discuss the results obtained in an extensive search for uranium-bearing particles embedded in lung tissues, collected at autopsy, of former uranium miners and millers. 13 references, 1 table.
Date: January 1, 1984
Creator: Paschoa, A.S.; Wrenn, M.E.; Singh, N.P.; Miller, S.C.; Jones, K.W.; Cholewa, M. et al.
Partner: UNT Libraries Government Documents Department