ASSESSEMNT OF BN-350 SPENT NUCLEAR FUEL STATUS IN CONDITIONS OF A LONG-TERM STORAGE

The article provides outputs of γ-spectrometric survey of containers containing nuclear spent fuel (SNF) of BN-350 reactor. Based upon a theoretical assessment, calculation results of dose fields of neutron and photon radiation produced by a single container with spent nuclear fuel are given, with various options of FA wall destruction and different rates of fuel fall. Initial values necessary for monitoring SNF status as well as the exposure time and a survey grid were determined. When comparing results of the theoretical assessment with experimental data, it was found that measurement points at a height of 2 m above the container bottom are optimal positions for the subsequent monitoring of SNF status in conditions of a long-term storage. These positions are the most representative and in case of fuel fall, this process will be shown in monitoring measurements.

1. Нечаев А., Онуфриев В., Томас К. Долговременное хранение и захоронение отработавшего топлива // Обращение с радиоактивными отходами: Бюл. МАГАТЭ. – 1986. – 17 с.

2. Briesmeister J.F. MCNP – a general Monte-Carlo Code for neutron and photon Transport. LA-7396M, 1997.

3. Гигиенические нормативы. «Санитарно-эпидемиологические требования к обеспечению радиационной безопасности». Утверждены приказом Министра национальной экономики Республики Казахстан от 27 февраля 2015 г.

4. ПБЯ-06-09-90. Правила ядерной безопасности при хранении и транспортировании ядерноопасных делящихся материалов: утв. Министерством атомной энергетики и промышленности 04 февраля 1991 г.