Expanding spent fuel storage facilities for CANDU reactors

This paper reviews the methods used to extend spent fuel storage facilities for CANDU reactors. AECL's experience has been focussed over a 15 year period on dry spent fuel storage in reinforced cylindrical concrete containers. AECL commenced to develop the dry storage method as an alternative to wet storage at Whiteshell Nuclear Research Establishment (WRNE) in 1974. During the subsequent years, concrete canisters were tested to store fuel from CANDU prototype and commercial reactors. Between 1984 and 1989 all spent fuel generated by AECL's prototype reactors (Gentilly-1, Douglas Point and NPD station) was safely and economically stored in concrete canisters, as part of the decommissioning activities. The four AECL designed CANDU 6 stations built in Canada (2), Korea and Argentina are gradually reaching their pool storage capacity of 10 years of reactor operation. Point Lepreau station in Canada has already opted for dry spent fuel storage technology instead of constructing an additional storage pool. The Ontario Hydro nuclear program relies on stations with multiple units which have common and large capacity spent fuel pools. The Pickering stations being the first units built will require supplementary spent fuel storage capacity in the early 1990's. Ontario Hydro is considering (among several options) dry storage in single concrete containers, which could be used for transportation and possibly for eventual disposal of spent fuel. AECL's dry storage technology is described as it evolved into its present state including the trend for development in the future. The factors influencing the evolution and the impact generated upon the design of AECL's future CANDU stations are highlighted. (author). 2 refs, 4 figs