Identification of locations with orphaned fissile materials within the exclusion zone

Customer: Battelle Energy Alliance LLC, U.S. DOE

Objective: develop investigation procedures for the storage facilities of nuclear materials and their quantity, sampling methods; develop measurement instructions; implement collection and analysis of samples; initial works for the materials characterization.

In 2014, we were developing the procedure for calculation of the amount of fuel disposed in concrete canyons at RWDS (“ChNPP Stage 3”).

Accomplishments:
• development of the mathematical computation for calculation of internal activity of a solid provided that only its surface dose values are available: a solid shall be divided into sections and activity of each one shall be calculated (single-point activity of a solid);
• development of the algorithm to find optimum dosimeter location points based on the table of sample solid surface measurements;
• development of the algorithm to calculate doses based on the previously known activity points;
• implementation of the mathematical model numerical solution: calculation of solid activity points;
• development of the algorithm: method of approximate calculation of total activity based on statistical sampling;
• development of the theoretical calculations to find variables required for the algorithm final calculations;
• development of the software code to carry out the procedure for approximate calculation of total activity based on statistical sampling;
• development of a practical example to demonstrate the dependencies identified in the procedural algorithm;
• preparation of the final document with a complete description of the procedure.