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Photon burst mass spectrometry--ultrasensitive detection of rare isotopes

Description: Progress is reported on the development of a new technique for measurement of trace levels of radioisotopes which is based on fluorescence detection of output from a mass spectrometer. Significant achievements include the observation of fluorescence and burst signals from Kr isotopes, including enriched samples of {sup 85}Kr with a 4-collector system. An abundance sensitivity is demonstrated with {sup 83}Kr and {sup 85}Kr.
Date: February 1, 1995
Creator: Hansen, C.S.; Pan, X.J.; Fairbank, W.M. Jr.; Oona, H.; Chamberlin, E.P.; Nogar, N.S. et al.
Partner: UNT Libraries Government Documents Department

Photon burst mass spectrometry for the measurement of {sup 85}Kr at ambient levels

Description: Photon Burst Mass Spectrometry has been used to measure {sup 85}Kr in a sample with an abundance of 6 x 10{sup {minus}9}. Improvements in detection efficiency by the use of avalanche photodiodes cooled to liquid nitrogen temperature are reported, which should make possible measurement of {sup 85}Kr at the ambient atmospheric abundance of 10{sup {minus}11}. Potential applications include nuclear monitoring, atmospheric transport, and dating young ground water up to 40 years.
Date: December 1, 1998
Creator: Fairbank, W.M. Jr.; LaBelle, R.D. & Hansen, C.S.
Partner: UNT Libraries Government Documents Department


Description: The objectives of gaseous waste management for the recycling of nuclear used fuel is to reduce by best practical means (ALARA) and below regulatory limits, the quantity of activity discharged to the environment. The industrial PUREX process recovers the fissile material U(VI) and Pu(IV) to re-use them for the fabrication of new fuel elements e.g. recycling plutonium as a Mixed Oxide (MOX) fuel or recycling uranium for new enrichment for Pressurized Water Reactor (PWR). Meanwhile the separation of the waste (activation and fission product) is performed as a function of their pollution in order to store and avoid any potential danger and release towards the biosphere. Raffinate, that remains after the extraction step and which contains mostly all fission products and minor actinides is vitrified, the glass package being stored temporarily at the recycling plant site. Hulls and end pieces coming from PWR recycled fuel are compacted by means of a press leading to a volume reduced to 1/5th of initial volume. An organic waste treatment step will recycle the solvent, mainly tri-butyl phosphate (TBP) and some of its hydrolysis and radiolytic degradation products such as dibutyl phosphate (HDPB) and monobutyl phosphate (H2MBP). Although most scientific and technological development work focused on high level waste streams, a considerable effort is still under way in the area of intermediate and low level waste management. Current industrial practices for the treatment of gaseous effluents focusing essentially on Iodine-129 and Krypton-85 will be reviewed along with the development of novel technologies to extract, condition, and store these fission products. As an example, the current industrial practice is to discharge Kr-85, a radioactive gas, entirely to the atmosphere after dilution, but for the large recycling facilities envisioned in the near future, several techniques such as 1) cryogenic distillation and selective absorption in solvents, 2) ...
Date: November 1, 2010
Creator: Paviet-Hartmann, Patricia; Kerlin, William & Bakhtiar, Steven
Partner: UNT Libraries Government Documents Department

Final deactivation report on the Radioactive Gas Processing Facility, Building 3033, and the Actinide Fabrication Facility, Building 3033A, at Oak Ridge National Laboratory, Oak Ridge, Tennessee

Description: The purpose of this report is to document the condition of Buildings 3033 and 3033A, after completion of deactivation activities as outlined by the Department of Energy Office of Nuclear Materials and Facility Stabilization Program (EM-60) guidance documentation. This report outlines the activities conducted to place the facility in a safe and environmentally sound condition for transfer to the Department of Energy Office of Environmental Restoration Program (EM-40). This report provides a history and profile of Buildings 3033 and 3033A prior to commencing deactivation activities and a profile of the building after completion of deactivation activities. Turnover items, such as the Post-Deactivation Surveillance and Maintenance Plan, remaining hazardous materials, radiological controls, Safeguards and Security, quality assurance, facility operations, and supporting documentation provided in the Office of Nuclear Materials and Facility Stabilization Program (EM-60) Turnover package are discussed. Buildings 3033 and 3033A will require access to facilitate required S and M activities to maintain the building safety envelope. Buildings 3033 and 3033A were stabilized during deactivation so that when transferred to the EM-40 program, only a minimal S and M effort would be required to maintain the building safety envelope. Other than the minimal S and M activities the building will be unoccupied and the exterior doors locked to prevent unauthorized access. The building will be entered only to perform the required S and M. All materials have been removed from the building, and all utility systems, piping, and alarms have been deactivated.
Date: September 1, 1997
Partner: UNT Libraries Government Documents Department

The radioactivity of atmospheric krypton in 1949--1950

Description: The chemical element, krypton, whose principal source is the atmosphere, had a long-lived radioactive content, in the mid 1940s, of less than 5 dis. per min. per liter of krypton. In the late 1940s this had risen to values in the range of a hundred dis. per min. per liter. It is now some hundred times higher than the late 1940 values. This radioactivity is the result of the dissolving of nuclear fuel for military and civilian purposes, and the release thereby of the fission product krypton-85 (half-life 10.73 years, fission yield about 0.2%). The present largest emitter of krypton-85 is the French reprocessing plant at Cap-de-la Hague.
Date: August 1, 1997
Creator: Turkevich, A.; Winsberg, L.; Flotow, H. & Adams, R.M.
Partner: UNT Libraries Government Documents Department

Subsurface novel gas transport at the Nevada Test Site

Description: This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The objective of our research was to explain the results of a groundwater pumping test done from 1975 to 1991 at the location of the nuclear test {open_quotes}Cambric{close_quotes} on the Nevada Test Site. The elution data from the pumped well indicated that krypton was delayed relative to tritium in the eluate and that less than half of the calculated Kr-85 source term was removed (though over 92% of the tritium was removed). We postulated an explanation for these observations and tested it with a mathematical model that simulated the movement of tritium and krypton at this site. The model showed that the hypothesis was consistent with the observed behavior; but the model was very sensitive to assumptions about initial radionuclide distributions and to hydrologic parameters. 1 ref.
Date: December 31, 1998
Creator: Thompson, J.L.; Guell, M.A. & Hunt, J.R.
Partner: UNT Libraries Government Documents Department

Atom trap trace analysis of krypton isotopes

Description: A new method of ultrasensitive isotope trace analysis has been developed. This method, based on the technique of laser manipulation of neutral atoms, has been used to count individual {sup 85}Kr and {sup 81}Kr atoms present in a natural krypton gas sample with isotopic abundances in the range of 10{sup {minus}11} and 10{sup {minus}13}, respectively. This method is free of contamination from other isotopes and elements and can be applied to several different isotope tracers for a wide range of applications. The demonstrated detection efficiency is 1 x 10{sup {minus}7}. System improvements could increase the efficiency by many orders of magnitude.
Date: November 17, 1999
Creator: Bailey, K.; Chen, C. Y.; Du, X.; Li, Y. M.; Lu, Z.-T.; O'Connor, T. P. et al.
Partner: UNT Libraries Government Documents Department

Atom trap trace analysis

Description: A new method of ultrasensitive trace-isotope analysis has been developed based upon the technique of laser manipulation of neutral atoms. It has been used to count individual {sup 85}Kr and {sup 81}Kr atoms present in a natural krypton sample with isotopic abundances in the range of 10{sup {minus}11} and 10{sup {minus}13}, respectively. The atom counts are free of contamination from other isotopes, elements,or molecules. The method is applicable to other trace-isotopes that can be efficiently captured with a magneto-optical trap, and has a broad range of potential applications.
Date: May 25, 2000
Creator: Lu, Z.-T.; Bailey, K.; Chen, C.-Y.; Du, X.; Li, Y.-M.; O'Connor, T. P. et al.
Partner: UNT Libraries Government Documents Department

Capability of environmental sampling to detect undeclared cask openings

Description: The goal of this study is to determine the signatures that would allow monitors to detect diversion of nuclear fuel (by a diverter) from a storage area such as a geological repository. Due to the complexity of operations surrounding disposal of spent nuclear fuel in a geologic repository, there are several places that a diversion of fuel could take place. After the canister that contains the fuel rods is breached, the diverter would require a hot cell to process or repackage the fuel. A reference repository and possible diversion scenarios are discussed. When a canister is breached, or during reprocessing to extract nuclear weapons material (primarily Pu), several important isotopes or signatures including tritium, {sup 85}Kr, and {sup 129}I are released to the surrounding environment and have the potential for analysis. Estimates of release concentrations of the key signatures from the repository under a hypothetical diversion scenario are presented and discussed. Gas analysis data collected from above-ground storage casks at Idaho National Engineering and Environmental Laboratory (INEEL) Test Area North (TAN) are included and discussed in the report. In addition, LANL participated in gas sampling of one TAN cask, the Castor V/21, in July 1997. Results of xenon analysis from the cask gas sample are presented and discussed. The importance of global fallout and recent commercial reprocessing activities and their effects on repository monitoring are discussed. Monitoring and instrumental equipment for analysis of the key signature isotopes are discussed along with limits of detection. A key factor in determining if diversion activities are in progress at a repository is the timeliness of detection and analysis of the signatures. Once a clandestine operation is suspected, analytical data should be collected as quickly as possible to support any evidence of diversion.
Date: December 1, 1997
Creator: Beckstead, L.W.; Efurd, D.W.; Hemberger, P.H.; Abhold, M.E. & Eccleston, G.W.
Partner: UNT Libraries Government Documents Department


Description: The diffusion of Kr/sup 85/ in two UO/sub 2/ powders was studied by performing a series of post-irradiation anneals on the powders. The emanation data were analyzed by considering the effect of sintering as well as the effect of a distribution of particle sizes within the sample. Measurements were made at 900 to 1500 deg C. The time at a temperature was between 8 and 24 hours. The diffusion coefficients for Kr/sup 85/ in the two powders are represented by the equations: D = 2.65 x 10/sup -4/ exp - 65,500/RT for UO/sub 2/ prepared from crushed UO/sub 2/ pellets and, for a chemically prepared UO/sub 2/ powder, D = 4.9 x 10/sup -4/ exp - 73,800/RT. (auth)
Date: February 1, 1960
Creator: Auskern, A.B.
Partner: UNT Libraries Government Documents Department

Final Report on the Pinot Experiment

Description: The Pinot Project was designed to provide some indication of the extent to which gases from a confined underground explosion in oil shale would migrate parallel to the bedding planes. At 0800 on Aug. 2, 1960, 946 lb of nitromethane was fired in shot hole No. 1. There was no visible damage to the mine adit or to any structure associated with cation of the extent to which gases from a confined underground explosion in oil shale would migrate parallel to the bedding planes. At 0800 on Aug. 2, 1960, 946 lb of nitromethane was fired in shot hole No. 1. There was no visible damage to the mine adit or to any stnucture associated with the workings. Gas samples collected from sampling holes near the shot hole were analyzed for Kr/sup 85/, which had been included with the nitromethane as a tracer. It appeared that the Kr/sup 85/ concentration in the samples out to 50 ft was more or less independent of space and time between +2 and +50 hr. Relativsly little Kr/sup 85/ was detected at 125 ft and none beyond. About (20 plus or minus 10)% of the Kr/sup 85/ escaped into ths adit. The results of the Pinot experiment cannot be extrapolated quantitatively to the case of a nuclear explosion in oil shale. Even if the structure at the Pinot site is typical of oil shale, the generation of a smaller quantity of noncondensible gases per unit energy in a nuclear explosion (as compared with a chemical explosion), the shonter time scale of the ensrgy release and the higher temperatares and pressures encountered will all have a definite influence on the effective containment distance. One can conclude, however, that, if the medium at the site of a potential nuclear experiment is similar to that at Pinot, ...
Date: December 27, 1960
Creator: Adelman, F. L.; Bacigalupi, C. M. & Momyer, F. F.
Partner: UNT Libraries Government Documents Department

Mound Laboratory Progress Report for May 1963

Description: Progress is reported on research directed toward. the development of adhesives, which are compatible with explosives; the measurement of nuclear properties of polonium isotopes; residue adsorption; separation and purification of isotopes; thermal diffusion theory analyses; emission strength analyses for neutron sources; and krypton-85 counting methods development. (B.O.G.)
Date: May 31, 1963
Creator: Eichelberger, J. F.; Grove, G. R.; Jones, L. V. & Rembold, E. A.
Partner: UNT Libraries Government Documents Department

Radionuclide air emissions. Annual report for calendar year 1997

Description: A description is provided of radioactive effluent releases from the Pinellas Plant. The DOE sold the Pinellas Plant in March 1995. A portion of the plant was backed by DOE until September 1997 to facilitate a safe transition to commercial ventures.The plant`s radiological processing equipment was cleaned from past DOE operations. Emissions from the cleanup activity were monitored.
Date: August 1, 1997
Partner: UNT Libraries Government Documents Department

Head-end reprocessing studies of H.B. Robinson-2 fuel: II. Parametric voloxidation studies

Description: A series of hot-cell tests was conducted with UO{sub 2} that had been irradiated to an average of 28,000 MWd/t in the H.B. Robinson-2 reactor of the Carolina Power and Light Company. The tests examined the effects of temperature and of the rate of oxygen supply on the release of gaseous and semivolatile fission products, while the fuel fragments were tumbled at 12 rpm during voloxidation - the high-temperature oxidation of UO{sub 2} to U{sub 3}O{sub 8}. The experiments showed that >99.9% of the tritium in the irradiated UO{sub 2} was released to the off-gas stream at temperatures of 480 and 550{sup 0}C and at oxygen feed rates ranging from 0.1 to 1.2 mol/h. The release of {sup 85}Kr varied from 2 to 7% of the fuel inventory. The U{sub 3}O{sub 8} product ({similar_to}99% smaller than 44 {mu}m) was easily dissolved in 7 M HNO{sub 3}. One 2-h leach in 7 M HNO{sub 3} dissolved {similar_to}99.5% of the heavy metals; a second 2-h leach in 7 M HNO{sub 3} brought the total to >99.98%. Voloxidation did not affect the final solubility of the uranium and plutonium but did increase the weight of the insoluble fission product residue from 0.18% of the irradiated UO{sub 2} to {similar_to}0.62%.
Date: May 1, 1980
Creator: Goode, J.H.; Stacy, R.G. & Vaughen, V.C.A.
Partner: UNT Libraries Government Documents Department

Comparisons of CAP88PC version 2.0 default parameters to site specific inputs

Description: The effects of varying the input for the CAP88PC Version 2.0 program on the total effective dose equivalents (TEDEs) were determined for hypothetical releases from the Hot Fuel Examination Facility (HFEF) located at the Argonne National Laboratory site on the Idaho National Engineering and Environmental Laboratory (INEEL). Values for site specific meteorological conditions and agricultural production parameters were determined for the 80 km radius surrounding the HFEF. Four nuclides, {sup 3}H, {sup 85}Kr, {sup 129}I, and {sup 137}Cs (with its short lived progeny, {sup 137m}Ba) were selected for this study; these are the radioactive materials most likely to be released from HFEF under normal or abnormal operating conditions. Use of site specific meteorological parameters of annual precipitation, average temperature, and the height of the inversion layer decreased the TEDE from {sup 137}Cs-{sup 137m}Ba up to 36%; reductions for other nuclides were less than 3%. Use of the site specific agricultural parameters reduced TEDE values between 7% and 49%, depending on the nuclide. Reductions are associated with decreased committed effective dose equivalents (CEDEs) from the ingestion pathway. This is not surprising since the HFEF is located well within the INEEL exclusion area, and the surrounding area closest to the release point is a high desert with limited agricultural diversity. Livestock and milk production are important in some counties at distances greater than 30 km from the HFEF.
Date: March 2, 2000
Creator: Lehto, M. A.; Courtney, J. C.; Charter, N. & Egan, T.
Partner: UNT Libraries Government Documents Department

Preliminary pathway analysis for YMP preclosure biosphere dose assessment

Description: The preliminary preclosure biosphere dose assessment for the Yucca Mountain Project (YMP) involves the calculation of a radiation dose to a subsistence farmer living near the proposed Yucca Mountain repository. Eight radionuclides, H-3, Co-60, Kr-85, Sr-90, Ru-106, I-129, Cs-134, and Cs-137, are considered in this study. Radiation doses resulting from unit release rates of these radionuclides are analyzed. Total dose has been broken down into components that result from various exposure pathways. By using this approach, the most important pathways that deliver a radiation dose to a subsistence farmer can be clearly identified.
Date: May 13, 1998
Creator: Wu, D.; Liu, N.; Tappen, J.J. & Tung, C.H.
Partner: UNT Libraries Government Documents Department

An aerial radiological survey of the Wright-Patterson Air Force Base and surrounding area, Fairborn, Ohio

Description: An aerial radiological survey was conducted over areas of Wright-Patterson Air Force Base (WPAFB) and the immediate surrounding area, during the period July 7 through 20, 1994. The survey was conducted to measure and map the gamma radiation in the area. This mission was the first aerial radiation survey conducted at WPAFB. In the surveyed area, five small localized sources of gamma radiation were detected which were atypical of naturally-occurring radionuclides. On WPAFB property, these sources included a radiation storage facility in Area B (krypton-85) and an ash pile near the Area C flight line (low energy gamma activity). In the area covered outside WPAFB boundaries, sources included cesium-137 in excess of worldwide fallout over a landfill in a northern Dayton industrial area, an X-ray radiography source over a steel plant in the same industrial area, and a mixture of cesium-137 in excess of worldwide fallout and possibly iridium-192 in an area near Crystal Lakes, Ohio. The naturally-occurring gamma emitters (uranium-238 and progeny, thorium and progeny, and potassium-40) were detected in the remaining area with a total exposure rate range of 4 to 16 {mu}R/h; this range is typical of that found in the United States, 1 to 20 {mu}R/h.
Date: August 1995
Partner: UNT Libraries Government Documents Department