Authors:D. DiPrete, C. DiPrete, N. Bibler, C. Bannochie, and M. Hay
Waste cleanup efforts underway at the United States Department of Energy’s (DOE) Savannah River Site (SRS) in South Carolina,
as well as other DOE nuclear sites, have created a need to characterize 79Se in radioactive waste inventories. Successful analysis of 79Se in high activity waste matrices is challenging for a variety of reasons. As a result of these unique challenges, the successful
quantification of 79Se in the types of matrices present at SRS requires an extremely efficient and selective separation of 79Se from high levels of interfering radionuclides. A robust 79Se radiochemical separation method has been developed at the Savannah River National Laboratory (SRNL) which is routinely
capable of successfully purifying 79Se from a wide range of interfering radioactive species. In addition to dramatic improvements in the Kd, ease, and reproducibility of the analysis, the laboratory time has been reduced from several days to only 6 h.
Authors:N. Bibler, W. Kinard, W. Boyce, and C. Coleman
Savannah River Site (SRS) is immobilizing the radioactive, high-level waste sludge in Tank 51 into a borosilicate glass for
disposal in a geologic repository. A requirement for repository aceeptance is that SRS report the concentrations of certain
fission product and actinide radionuclides in the glass. This paper presents measurements of many of these concentrations
in both Tank 51 sludge and the final glass. The radionuclides were measured by inductively coupled plasma mass spectrometry
and α, β, and γ counting methods. Examples of the radionuclides are90Sr,137Cs,238U and,239Pu. Concentrations in the glass are 3.1 times lower due to dilution of the sludge with a nonradio-active glass forming frit
in the vitrification process. Results also indicated that in both the sludge and glass the relative concentrations of the
long lived fission products insoluble in caustic are in proportion to their yields from the fission of235U waste in the SRS reactors. This allowed the calculation of a fission yield scaling factor. This factor in addition to the
sludge dilution factor can be used to estimate concentrations of waste acceptance radionuclides that cannot be measured in
the glass. Examples of these radionuclides are79Se,93Zr, and107Pd.
Authors:D. Beals, W. Britt, J. Bibler, and D. Brooks
The use of solid phase extraction (SPE) disks was studied for the quantification of selected radionuclides in aqueous solutions.
The extraction of four radionuclides using six types (two commerical, four test materials) of 3M EmporeTM RAD disks was studied. The radionuclides studied were: technetium-99 (two types of disks), cesium-137 (two types), strontium-90
(one type), plutonium-238 (one type). Extractions were tested from DI water, river water and seawater. Extraction efficiency,
kinetics (flow rate past the disk), capacity, and potential interferences were studied as well as quantification methods.
Authors:R. Dewberry, W. Boyce, N Bibler, A. Ekechukwu, and D. Ferrara
This paper describes development work to obtain a product phase of 151Sm pure of any other radioactive species so that it can be determined in US Department of Energy high level liquid waste and low level solid waste by liquid scintillation b-spectroscopy. The technique provides separation from mCi/ml levels of 137Cs, Pu a- and 241Pu b-decay activity, and 90Sr/90Y activity. The separation technique is also demonstrated to be useful for the determination of 147Pm.
Authors:W. Kinard, N. Bibler, C. Coleman, and R. Dewberry
Highly radioactive waste from defense-related activities at the Savannah River Site in South Carolina are to be incorporated into a borosilicate glass in the Defense Waste Processing Facility (DWPF) for long-tem geological isolation. Processing and repository safety considerations require the determination of 24 radioisotopes that meet the reporting criteria. These isotopes include fission products, activation products, and daughter nuclei that grow into the waste. Four isotopes,137Cs,90Sr,238Pu and238U will be routinely measured in the DWPF operation for process control. This work shows that the concentrations of the other 20 reportable radioisotopes in the final glass product can be predicted from a thorough characterization of the high level waste (HLW) tanks and a knowledge of the concentrations of the major non-radioactive components in the vitrification process.
in Nagydobrony (1938-1950)] In: Eksztázis, álom, látomás. [Ecstasy, Dream, Vision] Ed. Éva PÓCS, 147-155. Budapest-Pécs. 1999: The Image of the Other World in a Peasant Bible Paraphrase (Borbála Mikó's "Eternal Gospel"). In: Religious Movements and