Scientific and practical aspects of a radiation inspection for a decommissioned NPP unit

In connection with NPP service life requirements, an assessment of the radiation states of power units prior to their decommissioning becomes relevant. According to the regulatory documents, for these purposes, a comprehensive inspection of the unit should be carried out, whose results are used to assess the radiation impact on personnel during decommissioning, justifying and selecting the methods of decontamination, dismantling, and territorial reclamation, as well as to determine the volume of generated radioactive wastes. The radiation inspection of the first two units at the Leningrad NPP produced an adequate amount of initial data for the development of the decommissioning project. However, at the same time, it demonstrated the presence of significant difficulties associated with the lack of comprehensive requirements for the scope of instrumental and calculation works, inspection methods, as well as the analysis and processing of measurement and calculation results. In order to solve these problems, it is proposed to develop a standard methodology for the radiation inspection of decommissioned NPP units taking into account the experience gained at the Leningrad NPP.