Review calculations for the OECD/NEA Burn-up Credit Criticality Safety Benchmark

A calculation methodology for criticality safety evaluations related to medium term dry storage, e.g. interim storage, and long term waste disposal, e.g. deep geological repository, is under development at PSI. In that sense, the performance of present decay and criticality safety codes has to be evaluated for this kind of applications, with code to code, and data to data, comparison as a very first step. In this article, the Burn-up Credit Criticality Safety Benchmark Phase VII organized by OECD/NEA has been employed to evaluate decay calculations results for the codes CINDER and SERPENT2. The computed isotopic compositions have then been used for the assessment of the criticality calculations with MCNP6 and SERPENT2, while employing the most recent available cross sections libraries from ENDF/B-VII.1, JEFF-3.2 and TENDL-2014. Results show overall a good agreement for all the options listed, while differences are pointed out and their origin is discussed.