Interim Spent Fuel Storage (ISFS)
During the process of spent nuclear fuel management (SNF), the company JAVYS, a. s. ensures provision of services concerning storage, manipulation and monitoring of SNF. The company is the owner and operator of the nuclear facility Interim Spent Fuel Storage. Since 1987, the spent nuclear fuel from the VVER 440 type reactors has been safely stored in this facility by a method of wet storage for a period of at least 50 years and more, or until the final stage in the spent nuclear fuel management is implemented, consisting of the reprocessing of SNF or its direct storage in a deep repository.
From 1996 till 1999 the project of Interim Storage redesign was executed, with seismic retrofitting and expanding its storage capacity. At the same time important technological, control, electrical and safety systems, as well as radiation control systems were redesigned, the autonomous cooling circuit of pool water and own consumption diesel generator was completed, together with the system of fuel leak tightness control, system of civil and technological parts long term monitoring including spent nuclear fuel status monitoring. There is a project of completion of the spent nuclear fuel storage capacity in Jaslovské Bohunice site ensuring storage of all considered spent nuclear fuel from the Slovak reactor units in operation or under construction.
Interim spent fuel storage facility is a separate building. Its main part consists of four pools, connected by a manipulating channel. Spent nuclear fuel is stored in KZ-48 (or T13) type casks under a shielding layer of demineralized water which also serves as a cooling medium for the residual heat removal.
During storage and handling of the spent nuclear fuel in the Interim Storage, all the safety functions are ensured by the building constructions, technological equipment and other systems, designed so as to ensure nuclear and radiation safety of Interim Storage not only during normal operation but also in case of emergency.
Completion of Storage Capacity for Spent Nuclear Fuel
The completion of spent nuclear fuel storage capacity is proposed to by realized in two stages, with the first stage enhancing the storage capacity by at least 10,100 pieces of spent nuclear fuel and the second stage by a minimum of 8,500 pieces of spent nuclear fuel. The completed storage capacity is structurally connected to the current ISFS building. The spent nuclear fuel storing is proposed by a method of dry storage in hermetic canisters placed in the underground reinforced concrete storage modules.