O. V. Balan, L. I. Pavlovskyi, V. M. Rudko
Institute for Safety Problems of Nuclear Power Plants, NAS of Ukraine, 36a, Kirova st., Chornobyl, 07270, Ukraine
DOI: doi.org/10.31717/2311-8253.24.1.4
Abstract
The paper contains proposals for radioactively contaminated concrete structures (RCCS) management, which will be formed, removing fuel-containing materials (FCM) from the Shelter object. RCCS will be characterized by different intensity of radioactive contamination, which is only in the near-surface layer of concrete. In the case of containerized storage of such RW, significant costs will be required, first, for the fragmentation of RCCS in order to convert them into a loose form and for conducting dosimetric and radiometric measurements. A significant reduction in the total costs of handling RCCS can be achieved by burying the overall structures in the modules of the superficial storage by the bulk method, without additional fragmentation, followed by immobilization with a cement-sand or clay solution. The given approach for determining the specific activity of the entire concrete structure is based on conducting direct dosimetric and radiometric measurements and finding conversion coefficients, namely from the dose rate (DR, μSv /h) into radioactive surface pollution (RSP, Bq/m2). In order to convert the structure’s RSP into specific activity, it is necessary to distribute the volume of the radioactively contaminated part over the entire structure’s volume. The following are technical proposals for management and burying RCCS in a near-surface disposal facility with multi-barrier protection, which ensures reliable isolation of RCCS from the environment. It is noted the need to use safe technologies, which are based on the involvement of technical means and devices that make it possible to completely eliminate or minimize the involvement of personnel. Thus, the requirements of regulatory and operational-technical documents regarding the safe handling and disposal of RCCS must be met.
Keywords: ChNPP, NS C-SO, RCCS, surface pollution, specific activity, disposal
References
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