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Characterization of organics in leachates from low-level radioactive waste disposal sites

Description: Low-level radioactive wastes generated by the nuclear industry, universities, research institutions, and hospitals are disposed of in shallow-land trenches and pits. In 1962 the first commercial disposal site was opened in Beatty, Nevada. Since then, the industry has grown to include three private companies operating six disposal areas located in sparsely populated areas: at Maxey Flats (Morehead), Kentucky; Beatty, Nevada; Sheffield, Illinois; Barnwell, South Carolina; West Valley, New York; and Richland, Washington. Although the facilities are operated by private industry, they are located on public land and are subject to federal and state regulation. Although inventories of the radioactive materials buried in the disposal sites are available, no specific records are kept on the kinds and quantities of organic wastes buried. In general, the organic wastes consist of contaminated paper, packing materials, clothing, plastics, ion-exchange resins, scintillation vials, solvents, chemicals, decontamination fluids, carcasses of experimental animals, and solidification agents. Radionuclides such as /sup 14/C, /sup 3/H, /sup 90/Sr, /sup 134/ /sup 137/Cs, /sup 60/Co, /sup 241/Am, and /sup 238/ /sup 239/ /sup 240/Pu have been identified in leachate samples collected from several trenches at Maxey Flats and West Valley. The purpose of this report is to identify some of the organic compounds present in high concentrations in trench leachates at the disposal sites in order to begin to evaluate their effect on radionuclide mobilization and contamination of the environment.
Date: January 1, 1979
Creator: Francis, A.J.; Iden, C.R.; Nine, B. & Chang, C.
Partner: UNT Libraries Government Documents Department

Long-term leach rates of glasses containing actual waste

Description: Leach rates of borosilicate glasses that contained actual Savannah River Plant waste were measured. Leaching was done by water and by buffer solutions of pH 4, 7, and 9. Leach rates were then determined from the amount of /sup 137/Cs, /sup 90/Sr, and Pu released into the leach solutions. The cumulative fractions leached were fit to a mathematical model that included leaching by diffusion and glass dissolution.
Date: January 1, 1979
Creator: Wiley, J.R. & LeRoy, J.H.
Partner: UNT Libraries Government Documents Department

Respiratory tract tumors in Syrian hamsters following inhalation of Pu--ZrO/sub 2/ particles. [Comparison with incidence of lung tumors following intravenous injection of PuO/sub 2//ZrO/sub 2/ microspheres]

Description: Inhalation of radionuclide-bearing particles remains one of the most intensely pursued problems concerning the nuclear industry. This route of entry is generally accepted as the most probable, in case of human exposure, with ingestion being the other prominent source of concern. Many laboratory investigations, such as those reported here, continue to evaluate the possible consequences that may present health problems to the public domain. Syrian hamsters of both sexes received either inhaled (INH) PuO/sub 2//ZrO/sub 2/ particles, intravenous (IV) PuO/sub 2//ZrO/sub 2/ microspheres, a combination of INH PuO/sub 2//ZrO/sub 2/ particles and injected PuO/sub 2//ZrO/sub 2/ microspheres, or no radionuclides (controls). The INH particles and IV microspheres were tagged with ..gamma..-emitting /sup 57/Co to facilitate whole body counting and establishment of retention curves. Total lung burdens ranged from 8 nCi to 143 nCi. Significant numbers of primary lung tumors (5 to 50% per group) were induced in those animals that received INH exposures. Additional ..cap alpha.. radiation administered via Pu-laden IV microspheres had little or no effect on tumor production or nonneoplastic, degenerative changes in the respiratory tract.
Date: January 1, 1979
Creator: Thomas, R.G. & Smith, D.M.
Partner: UNT Libraries Government Documents Department

Imprecision of dose predictions for radionuclides released to the atmosphere: an application of the Monte Carlo-simulation-technique for iodine transported via the pasture-cow-milk pathway

Description: The shortcomings of using mathematical models to determine compliance with regulatory standards are discussed. Methods to determine the reliability of radiation assessment models are presented. Since field testing studies are impractical, a deficiency method, which analyzes the variability of input parameters and the impact of their variability on the predicted dose, is used. The Monte Carlo technique is one of these methods. This technique is based on statistical properties of the model output when input parameters inserted in the model are selected at random from a prescribed distribution. The one big assumption one must make is that the model is a correct formulation of reality. The Gaussian plume model for atmospheric transport of airborne effluents was used to study the pasture-cow-milk-man exposure pathway and the dose calculated from radioiodine (/sup 131/I) transported over this pathway. (DMC)
Date: January 1, 1979
Creator: Schwarz, G. & Hoffman, F.O.
Partner: UNT Libraries Government Documents Department

Radiochemical investigations of nuclear properties. Progress report, October 1, 1977--December 31, 1978. [Summaries of research activities at Purdue Univ]

Description: Results of (..cap alpha..,xn..gamma..) and (Heavy Ion, xn..gamma..) investigations of high spin excitations in spherical and transitional heavy nuclei are summarised. Considerable progress was made in studies of the level structures of /sup 187/,/sup 188/,/sup 189/Pt and of /sup 200/,/sup 201/,/sup 202/Pb. Investigations of the structure of the Z = 64, N = 82 nucleus /sup 146/Gd and of other nuclei consisting of the /sup 146/Gd core plus one, two or three valence nucleons are also briefly described. A list of publications is included.
Date: January 1, 1979
Creator: Daly, P.J.
Partner: UNT Libraries Government Documents Department

Spectroscopy of heavy nuclei: yrast states, side bands and backbending. [Transitions]

Description: Some recent experimental results concerning the high spin structure of two rare earth nuclei are presented. These are /sup 154/Er and /sup 158/Dy. The level schemes including yrast sequences are discussed. The reactions /sup 142/Nd(/sup 16/O,4n) and /sup 150/Nd(/sup 13/C,5n) respectively, for the studied nuclei are noted. 14 references. (JFP)
Date: January 1, 1979
Creator: Sunyar, A.W.
Partner: UNT Libraries Government Documents Department

Evaluation of the health hazard from inhaled krypton-85

Description: Evaluation of the degree of internal radiation hazard requires knowledge of the parameters of Kr-85 metabolism in human beings. Data on the rate of saturation and desaturation of the body tissues are required for this estimation. The object of this in vivo study was to characterize the metabolism of inhaled Kr. For this purpose, measurements were made of the distribution and clearance of Kr following inhalation of /sup 79/Kr by the normal subjects. The rate constants determined for /sup 79/Kr were used to calculate the radiation dose associated with exposure to the long-lived /sup 85/Kr. The retention data were obtained with the Brookhaven whole-body counter. The clearance of /sup 79/Kr from the body indicates five components ranging in half-times from 14 sec to 9.6 h. The slowest components, varying between 4.2 and 9.6 h, correlated highly with percent body fat. The long-term retention was localized in regions of high fat content. The stimated radiation dose based on the retention data of this study indicates that doses to body fat and gonads are larger than those estimated by other investigators. This increased estimated dose derives from the increase in retention time of krypton in fat pools.
Date: January 1, 1979
Creator: Cohn, S.H.; Ellis, K.J. & Susskind, H.
Partner: UNT Libraries Government Documents Department

Study of the replacement collision probability in the case of Co inplanted in Al at 4. 2/sup 0/K

Description: Earlier Moessbauer effect experiments on /sup 57/Co diffused in Al show two different positions for the Co-atoms after irradiation of the sample with fast neutrons: substitutional Co and interstitial Co. In order to study the landing dynamics of Co in Al we have implanted /sup 57/Co in Al at 4.2/sup 0/K, at which temperature the Al-interstitials are still immobile. The total implanted dose was 10/sup 14/ at/cm/sup 2/, the implantation energy 85 keV. The Moessbauer spectrum shows one line corresponds to substantial Co-atoms, the other one comes from interstitial Co-atoms (in the <100> Co--Al mixed dumbbell position). The population of the substitutional site, found to be 0.46 +- 0.02, can give information on the interaction potentials between Co--Al and Al--Al when the results are interpreted on the basis of a replacement collision model modified by taking into account a spontaneous trapping volume for the lattice atom recoil, around substitutional Co.
Date: January 1, 1979
Creator: Odeurs, J.; Pattyn, H.; Verbiest, E.; Coussement, R.; Reintsema, S.R. & Brice, D.K.
Partner: UNT Libraries Government Documents Department