60Co content in the spent graphite masonry of commercial reactors at the siberian chemical combine

• Published in: Atomic energy (New York, N.Y.) N.Y.), 1999-03, Vol.86 (3), p.183-188
• Main Authors: Bushuev, A. V., Verzilov, Yu. M., Zubarev, V. N., Proshin, I. M., Petrova, E. V., Aleeva, T. B., Dmitriev, A. M., Zakharova, E. V., Ushakov, S. I., Baranov, I. I., Kabanov, Yu. I., Kolobova, É. I., Nikolaev, A. G.
• Format: Article
• Language: English
• Subjects: Contamination; Graphite; Masonry; Radioactive pollution; Reactors; Spectrometry; Uranium
• ISSN: 1063-4258; 1573-8205
• DOI: 10.1007/BF02672944

Some results of comprehensive investigations of the radioactive contamination of graphite masonry from shutdown commercial uranium-graphite reactors at the Siberian Chemical Combine are reported. The objective of the investigations was to study the distribution of radionuclides and to determine the contamination level. In the present paper information about^sup 60^Co in the gaphite of the I-1 and Él-2 reactors is reported. Its content in the samples was measured by γ-spectrometry. There were about 250 graphite samples from the I-1 reactor and 200 from Él-2. According to the data obtained, the surface contamination level of the blocks can be taken as the same for the entire core within the limits of the errors presented. The average^sup 60^Co contamination of the graphite in the surface of blocks from the I-1 core is 5600 ^sub -500^ ^sup +550^ Bq/g and 8400 ^sub -1000^ ^sup +1200^ Bq/g for the Él-2 core. The^sup 60^Co content in the interior volume of the graphite blocks of a I-1 reactor is now 1100 ^sub -160^ ^sup +200^ Bq/g and 2000 ^sub -300^ ^sup +1350^ Bq/g in ÉI-2. The^sup 60^Co activity in all blocks from the I-1 core is 1.22·10^sup 12^ Bq, and for ÉI-1 the figure is 2.16·10^sup 12^ Bq. 4 figures, 3 tables, 7 references.[PUBLICATION ABSTRACT]