Characterization of spent fuel approved testing material---ATM-105

Abstract

Printed in the UnitedGJ/kgM(28 MWd/kgM) and expected fission gas release of about i%. Characterizationdata includeI) descriptionsof as-fabricatedfuel design, irradiation history, and subsequentstorage and handling;2) isotopicgamma scans;3) fission gas analyses;4) ceramographyof the fuel and metallographyof the clac_ding; 5) special fuel studies involvinganalyticaltransmissionelectron microscopy (AEM); 6) calculatednuclide inventoriesand radioactivitiesin th,afuel and cladding;and 7) radiochemicalanalyses of the fuel and cladd"Jng. Additionalanalysesof the fuel are being conducted and will be _,ncluded in planned revisionsof this report.iii ACKNOWLEDGMENTS

Fukushima Daiichi reactor source term attribution using cesium isotope ratios from contaminated environmental samples

“…Variation in the expected 135 Cs/ 137 Cs isotope ratio as a function of fuel rod height in a typical boiling water reactor. Red lines show the general trend in 137 Cs activities across the fuel rod, while black data points represent 135 Cs/ 137 Cs isotope ratios as reported by Guenther et al . (note that 137 Cs activities represent the values measured by Guenther et al .…”

“…(note that 137 Cs activities represent the values measured by Guenther et al . ; exact 137 Cs activities in the center of the fuel were determined to be of the order of 10 9 Bq/g fuel). Errors represent 2σ.…”

“…In the case of source term attribution of environmental Cs contamination following reactor accidents, consider two end member accident scenarios: Rapid power excursion and/or rapid loss of coolant: in this scenario, fuel rods would be expected to undergo melting and/or cladding failure first at the point where the power/heat load is the highest (e.g. the centers of the fuel rods where the 135 Cs/ 137 Cs profiles tend to be very consistent), with damage to other portions of the core probably occurring immediately thereafter. Under these conditions the 135 Cs/ 137 Cs composition released would be expected to be very similar to those predicted for total core 135 Cs/ 137 Cs ratio estimates via ORIGEN. Gradual coolant loss over the course of minutes to hours: in this scenario, fuel melting and/or cladding failure would be expected to occur at the tops of the fuel rods first (due to their loss of cooling capabilities before the center of the core).…”

Review and Prioritization of Technical Issues Related to Burnup Credit for LWR Fuel

“…40,49 The majority of these measurements have been used to determine the biases and uncertainties of computational methods. 24%26 In addition, Ref.…”

Initial Results from Dissolution Testing of Various Air-Oxidized Spent Fuels

“…3 If that occurs, fission products such as Cs and I, which may be associated with gas bubbles, would become more accessible for (a) LWR spent fuel oxidized in air at 110 to 200 0 C approaches a stoichiometry of -U02. 4 , but has the cubic crystal structure of U 4 0 9 . 2 dissolution.…”