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Cesium in the Savannah River Site environment

Description: Cesium in the Savannah River Site Environment is published as a part of the Radiological Assessment Program (RAP). It is the fourth in a series of eight documents on individual radioisotopes released to the environment as a result of Savannah River Site (SRS) operations. The earlier documents describe the environmental consequences of tritium, iodine, and uranium. Documents on plutonium, strontium, carbon, and technetium will be published in the future. These are dynamic documents and current plans call for revising and updating each one on a two-year schedule.Radiocesium exists in the environment as a result of above-ground nuclear weapons tests, the Chernobyl accident, the destruction of satellite Cosmos 954, small releases from reactors and reprocessing plants, and the operation of industrial, medical, and educational facilities. Radiocesium has been produced at SRS during the operation of five production reactors. Several hundred curies of [sup 137]Cs was released into streams in the late 50s and 60s from leaking fuel elements. Smaller quantities were released from the fuel reprocessing operations. About 1400 Ci of [sup 137]Cs was released to seepage basins where it was tightly bound by clay in the soil. A much smaller quantity, about four Ci. was released to the atmosphere. Radiocesium concentration and mechanisms for atmospheric, surface water, and groundwater have been extensively studied by Savannah River Technology Center (SRTC) and ecological mechanisms have been studied by Savannah River Ecology Laboratory (SREL). The overall radiological impact of SRS releases on the offsite maximum individual can be characterized by total doses of 033 mrem (atmospheric) and 60 mrem (liquid), compared with a dose of 12,960 mrem from non-SRS sources during the same period of time. Isotope [sup 137]Cs releases have resulted in a negligible risk to the environment and the population it supports.
Date: March 1, 1992
Creator: Carlton, W.H.; Bauer, L.R.; Evans, A.G.; Geary, L.A.; Murphy, C.E. Jr.; Pinder, J.E. et al.
Partner: UNT Libraries Government Documents Department

Influence of point defects on grain boundary diffusion in oxides

Description: The influence of point defects on grain boundary diffusion of Co ions in NiO was studied using polycrystalline films and bicrystals. Grain boundary diffusion was studied at 750 C at oxygen partial pressure. Two diffusion regions were found. At low oxygen pressures, extrinsic diffusion was observed. Above oxygen pressure of 10{sup {minus}7}, influence of intrinsic point defects was detected. It was determined that grain boundary diffusion was > 3 orders of magnitude faster than volume diffusion. However, it seems that grain boundary diffusion is influenced by the point defects in a similar way as the volume diffusion. 4 figs.
Date: March 15, 1991
Creator: Stubican, V. S.
Partner: UNT Libraries Government Documents Department

Iodine-131 in irradiated fuel at time of processing from December 1944 through December 1947

Description: The purpose of this document is to provide a record of the iodine-131 releases that were used as source terms in calculating the Phase 1 air pathway doses. The following table provides estimates of monthly iodine-131 releases to the atmosphere from the irradiated fuel processing plants for the time period December 1944 (the first month of dissolution of irradiated fuel from the Hanford Site) through December 1947. The estimated values of iodine-131 contained in the irradiated fuel at the time of processing were calculated using the best available information. Details of the calculations, including the assumptions required to obtain the values and the inherent uncertainties in the values, will be addressed in a Phase 2 HEDR report. The quantity of iodine-131 is released to the atmosphere is obtained by multiplying the calculated iodine-131 content of the fuel being dissolved by a release fraction. The actual release fraction value is uncertain. The release fractions assumed for iodine-131 were based on values that are expected to bound the actual release of iodine-131. The Phase 1 dose estimates from iodine-131 were based on a most probable release factor of 75% with an upward uncertainty bound of 85% and a lower uncertainty bound of 50%. The values shown in the table were input to the Phase 1 Modular Dose Calculation Model, which provided the air pathway doses. 1 tab.
Date: March 1, 1991
Creator: Heeb, C.M. & Morgan, L.G.
Partner: UNT Libraries Government Documents Department

Radiographic inspections at the Calipatria Geothermal Test Site

Description: A report is given of radiographic inspections to estimate the extent of corrosion and scale buildup at the Geothermal Test Site in Calipatria, California. Radiation exposure techniques using /sup 60/Co and /sup 192/Ir isotopes were developed. Radiography safety procedures were established. Five radiographic evaluations were made of the Geothermal Test Site from May 1976 to February 1977. Estimations of scale buildup from radiographs of operating plant pipes, valves, and tanks correlated closely with our actual scale measurements from used plant sections.
Date: March 8, 1978
Creator: Durbin, P.F.
Partner: UNT Libraries Government Documents Department

Influence of humic-acid complexing on the mobility of Americium in the soil aquatic environment

Description: Diffusion data indicate the Am, Cm and Np migrate 1.2, 0.8, and 26 centimeters, respectively, in a thousand years. Thus, excluding mass transport by moving water or wind, actinide elements, such as Cm, Am, and Np that find their way to the soil-aquatic environment are relatively immobile. Measured diffusion coefficients, corrected for distribution between the aqueous and soil phases, tortuosity, negative absorption, and relative fluidity are in reasonable agreement with aqueous diffusion coefficients. However, agreement depends strongly on measurement method used to determine distribution ratios. Two sets of experiments with /sup 241/Am and /sup 152/Eu tracers have been done to measure distribution ratios as a function of the aqueous humic acid concentration. In the first experiments the solid phase was kaolinite and in the second series of distribution ratios were measured with Burbank sandy loam. Both of these experiments indicated that Am(III) and Eu(III) form very strong humic acid complexes with formation constants of approximately 10/sup 5/. Additional experiments are being done to establish the average number of Am(III)s or Eu(III)s bound to the humic acid polymer.
Date: March 1, 1982
Creator: Sheppard, J.C.; Campbell, M.J. & Kittrick, J.A.
Partner: UNT Libraries Government Documents Department

Pacific Northwest Laboratory monthly report on the strontium heat source development program, Division of Nuclear Research and Applications for February 1977. [WESF /sup 90/SrF/sub 2/ capsules]

Description: At Hanford, strontium is separated from the high-level waste, converted to the fluoride, and doubly encapsulated in small, high-integrity containers for subsequent long-term storage. The fluoride conversion, encapsulation and storage take place in the Waste Encapsulation and Storage Facilities (WESF). The encapsulated strontium fluoride represents an economical source of /sup 90/Sr if the WESF capsule can be licensed for heat source applications under anticipated use conditions. The objectives of this program are to obtain the data needed to license /sup 90/SrF/sub 2/ heat sources and specifically the WESF /sup 90/SrF/sub 2/ capsules. Research progress is reported on; (1) chemical and physical properties of /sup 90/SrF/sub 2/; (2) /sup 90/SrF/sub 2/ compatibility studies; and (3) capsule qualification and licensing.
Date: March 1, 1977
Creator: Fullam, H. T.
Partner: UNT Libraries Government Documents Department

Laser isotope separation by selective excited state photochemistry. Annual progress report, March 31, 1976--February 28, 1977

Description: Experimental results are presented providing insight into the mechanisms of photochemical separation of Cd isotopes by selective excitation of ICl in the presence of halogenated olefins. The types of scrambling reactions that can be expected in isotope separation by scavenging are discussed along with strategies for minimizing such reactions. The experimental results are summarized and the reaction mechanisms are represented by graphic equations. (JRD)
Date: March 1, 1977
Creator: Zare, R. N.
Partner: UNT Libraries Government Documents Department

Radionuclides in plankton from the South Pacific Basin

Description: We have initiated an investigation of the utility of marine plankton as bioconcentrating samplers of low-level marine radioactivity in the southern hemisphere. A literature review has shown that both freshwater and marine plankton have trace element and radionuclide concentration factors (relative to water) of up to 10/sup 4/. We participated in Operations Deepfreeze 1981 and 1982, collecting a total of 48 plankton samples from the USCGC Glacier on its Antarctic cruises. Battelle Pacific Northwest Laboratories sampled air, water, rain, and fallout. We were able to measure concentrations in plankton of the naturally-occurring radionuclides /sup 7/Be, /sup 40/K, and the U and Th series, and we believe that we have detected low levels of /sup 144/Ce and /sup 95/Nb in seven samples ranging as far south as 68/sup 0/. Biological identification of the plankton suggests a possible correlation between radionuclide concentration and the protozoa content of the samples. 7 references, 5 figures.
Date: March 23, 1984
Creator: Marsh, K.V. & Buddemeier, R.W.
Partner: UNT Libraries Government Documents Department

UCB-NE-107 user's manual

Description: The purpose of this manual is to provide users of UCB-NE-107 with the information necessary to use UCB-NE-107 effectively. UCB-NE-107 is a computer code for calculating the fractional rate of readily soluble radionuclides that are released from nuclear waste emplaced in water-saturated porous media. Waste placed in such environments will gradually dissolve. For many species such as actinides and rare earths, the process of dissolution is governed by the exterior flow field, and the chemical reaction rate or leaching rate. However, for readily soluble species such as /sup 135/Cs, /sup 137/Cs, and /sup 129/I, it has been observed that their dissolution rates are rapid. UCB-NE-107 is a code for calculating the release rate at the waste/rock interface, to check compliance with the US Nuclear Regulatory Commission's (USNRC) subsystem performance objective. It is an implementation of the analytic solution given below. 5 refs., 2 figs.
Date: March 1, 1989
Creator: Lee, W.W.L.
Partner: UNT Libraries Government Documents Department