Andreeva Bay: Outdoor storage of spent nuclear fuel

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In 1984, about 20 containers of spent nuclear fuel assemblies were unloaded onto this storage pad. The rest of them were moved to an outdoor concrete pad where the tanks utilised for dry storage are located. The concrete surface of the ground becomes deformed because of the friable soil. According to data from Minatom’s division for the management of spent nuclear fuel, the outdoor ground site is storing about 220 spent nuclear fuel assemblies from the first generation submarines in TK-6 (TK-11) type containers. Seven spent nuclear fuel assemblies in one of the containers are probably damaged. This was confirmed when one of the containers was being lifted and the plug in its bottom side and a part of an assembly fell out.

The generally poor technical condition of the containers and the lack of a licence authorised by the nuclear regulatory (GAN) preclude any transportation of the containers. Therefore, the unloading of fuel can only be conducted on the site. It is difficult to predict the challenges and problems that can arise during the unloading of the fuel. For example, problems can arise if the fuel elements of the assemblies are not fastened to the top of them. In this case it would be necessary to open the plug in the down side of the container so as to extract the spent nuclear fuel assembly. If the assembly is undamaged, then unloading of the fuel can continue according to the regular steps:

  • The container is placed on a horizontal pad;
  • The lid of the container is opened;
  • The spent nuclear fuel assembly is extracted from the container and reloaded into the transport cask, which then is placed into a shield container;
  • The shield container with transport casks is transported to the loading point where it will be placed aboard a nuclear service ship.

Due to the lack of special tools, the operation is conducted manually, using devices allowing the personnel to keep a safe distance from the immediate vicinity to the assemblies.