L. I. Pavlovsky1, D. O. Khomenko1,2, V. V. Yehorov1
1 Institute for Safety Problems of Nuclear Power Plants,
NAS of Ukraine, 36a, Kirova st., Chornobyl, 07270, Ukraine
2 Institute of Mathematical Machines and Systems Problems of the
NAS of Ukraine, 42, Acad. Hlushkova ave., Kyiv, 03187, Ukraine
As of the beginning of 2022, the first stage of transformation of the Shelter object (SO) into an ecologically safe system has been completed, i. e. the NSC-SO complex has been designed, built and put into operation. As a result of the work carried out, the risk of radiation and environmental safety of the Shelter object, as well as the NSC-SO complex as a whole, has significantly decreased, but it still remains and is quite significant. The reason for this is the existing unstable structures of the SO, which were installed in 1986. In 2021, the process of designing measures to dismantle unstable structures of the SO began. At the first stage of design, pre-design studies, characteristics of the radiation situation in the areas of construction and dismantling works were performed. The results of radiation research will be used in the development of technological design solutions. Various methods and techniques of dosimetric measurements were used in the research, which allowed performing work in virtually inaccessible places and in areas where the dose rate (DR) exceeded 30 mSv/h. Measurements were carried out by specialists of the Institute for Safety Problems of Nuclear Power Plants of the NAS of Ukraine using unique dosimetric equipment and devices that were purchased or manufactured on the basis of the Institute. As a result of researches, the characteristics of a radiation situation on workplaces of the future activity on dismantle of unstable structures of the SO are received. The amount of data obtained is sufficient to develop design guidelines for “early” dismantling of unstable structures. In the design process, it may be necessary to clarify some indicators of the radiation situation. Radiation measurements were performed in the period from September 2021 to December 2021.
Keywords: research, ISP NPP, dismantling, unstable structures, dose rate values, angular distribution of gamma radiation, surface radioactive contamination, concentration of radioactive aerosols, NSC-SO complex.
1. Report on the safety status of the Shelter object in 2008. SIP-P-PM-22–460-SAR-124–05. (in Rus.)
2. New Safe Confinement (NSC). Starting complex 2 (SC-2). Dismantling of unstable structures of the Shelter object of the ChNPP chipboard facility as part of the “early” dismantling. (in Ukr.)
3. Report on the implementation of pre-project studies at the site. Book 2: Study of the radiation situation. Radiation inspection of structures subject to “early” dismantling. Examination of possible sites for temporary storage of dismantled radioactive waste and routes for their transportation from the work area to storage sites. SIP09-2-001 NI 03 RPT 135 01. (in Rus.)
4. Working project on stabilization. Final report on radiation safety. SIP K 03 01 000 RSR003 03. 15.12.03. (in Rus.)
5. Batiy V. G., Stojanov A. I., Pravdivyy A. A., Kopanetc I. M., Selukova V. V., Savchuk O. G. (2007). [Determination of characteristics of surface contaminated objects in case of strong gamma background]. Problems of Nuclear Power Plants Safety and of Chornobyl, vol. 8, pp. 150–153. (in Rus.)
6. Yehorov V. V., Morozov Yu. V., Pavlovsky L. I., Kholodiuk A. О. (2017). [Change of radiation conditions at the Shelter object after setting of arch construction]. Problems of Nuclear Power Plants Safety and of Chornobyl, vol. 28, pp. 75–81. (in Ukr.)
7. Basic sanitary rules for ensuring radiation safety of Ukraine (OSPRBU-05). Кyiv, 2005, 141 p. (in Ukr.)
If the article is accepted for publication in the journal «Industrial Heat Engineering» the author must sign an agreement on transfer of copyright. The agreement is sent to the postal (original) or e-mail address (scanned copy) of the journal editions.
Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License International CC-BY that allows others to share the work with an acknowledgement of the work’s authorship and initial publication in this journal.