National Atomic Energy Agency

The first article, entitled " On the depletion of gadolinium-bearing fuel rods in BWR assemblies: a study within the NEA/OECD benchmark", presents the results of calculations obtained using the SCALE 6.2.2 code package, carried out as part of the international benchmark of the NEA/OECD . The purpose of this benchmark was to validate the computer codes for modeling the burnup of boiling water reactor fuel, containing gadolinium as a burnable absorber. The results of the analyses showed very good agreement with the results of other benchmark participants, correctly mapping both general trends and detailed changes in the neutron multiplication factor and concentrations of key gadolinium isotopes as a function of fuel burnup ratio. This work is another confirmation that Poland has the appropriate knowledge and computational tools to perform safety analyses of reactors at the highest global level.

In the second article, entitled "Backup power generators with diesel engines in nuclear power plants. Part 1", discusses the extremely important issue of ensuring reliable power sources in nuclear power plants in the event of a major power system failure. This applies to situations where  a nuclear power plant is completely cut off from the external power grid and its own needs are not met by a turbogenerator. The paper describes in detail the technology of diesel-powered generators that provide reliable power to key nuclear safety systems. It also refers to the IAEA Safety Standards and the legal regulations in force in Poland and the United States governing this issue.

The third article, entitled "Emergency planning zones for nuclear heat production: patterns from China, Finland and Switzerland and the path to decarbonization of Polish heating networks", continues the discussion from previous issues of the bulletin on the principles of creating emergency planning zones around nuclear power plants. The author analyses the different regulatory models used in China, Finland and Switzerland, showing how different legal systems combine radiation safety requirements with the needs of urban heating networks. Studies have shown that both large power units and small modular reactors (SMRs) can supply heating networks without the need to change the approach to setting emergency planning zones, provided that the heating medium comes from an inactive circuit.

The issue closes with an article in the English version, entitled "Radiological monitoring of the soil in the proximity of National Radioactive Waste Repository in Różan in years 2014–2023", which discusses the results of soil contamination measurements carried out in 2014-2023 around the National Radioactive Waste Repository in Różan, as part of the systematic radiation monitoring of the environment around this facility.