INSIDER Work Package 5 - Use Case 2 (BR3 Biological shield): Exercise performed by the SCK-CEN

The INSIDER Project (Improved Nuclear SIte characterisation for waste minimisation in Decommissioning and Dismantling operations under constrained EnviRonment) aims to develop and validate a new and improved integrated characterization methodology and strategy during nuclear decommissioning and dismantling operations (D&D) of nuclear power plants, post-accidental land remediation or nuclear facilities under constrained environments. Under Work Package 5 “In Situ Measurements”, an inter-comparison exercise is prepared for the characterization of the biological shield of the reactor vessel of the BR3 research reactor under decommissioning at the SCK-CEN. For this purpose, the following measurements are required: - Ambient Dose Equivalent Rate, H*(10), at contact: 25 measurements (5x5) for each of three different points (A, B, and C). - Total gamma activity (Bq/cm2) at contact: 25 measurements (5x5) for each of three different points (A, B, and C). - Activity Concentration (Bq/g or Bq/m2) for isotopes of interest at 30 cm: open and close collimation measurements for point C. This document summarizes the results obtained for the different measurements, and presents the equipment and methodology used.