2009 Report to Government on National Research and

suitable for uranium metal fuels. It would thus be necessary <strong>to</strong> carry out a
substantial (and successful) programme of R&D in<strong>to</strong> new encapsulants, such
as polymers, glasses and alternative cements, before this option could be
pursued. This would need <strong>to</strong> include R&D <strong>to</strong> demonstrate that the selected
encapsulation system was suitable for geological disposal.
A.22 Even in the event that the reprocessing strategy proceeds <strong>to</strong> 'completion', it is
inevitable that there will be some spent Magnox fuel that cannot be reprocessed
(Defra & NDA, 2008a). In particular, the corroded and degraded fuel from the
legacy ponds and silos at Sellafield (CoRWM docs. 2418, 2520) will have <strong>to</strong> be
treated as waste. R&D is in progress on suitable conditioning and packaging
options for legacy ponds and silos waste, in parallel with the development of
methods <strong>to</strong> retrieve it (CoRWM doc. 2520; NDA, 2008a). Reducing the hazards
associated with the Sellafield legacy ponds and silos has been identified as a
matter of urgency by the regula<strong>to</strong>rs and NDA has prioritised funding <strong>to</strong> undertake
the necessary work as quickly as possible (NDA, <strong>2009</strong>a, d).
AGR Fuel
A.23 AGR fuel consists of low-enriched uranium oxide pellets in stainless steel
cladding with graphite sleeves. For management purposes it is divided in<strong>to</strong> two
tranches, referred <strong>to</strong> as "his<strong>to</strong>ric" and "new" (CoRWM doc. 2419). The former
includes all AGR fuel loaded in<strong>to</strong> reac<strong>to</strong>rs on and before 14 January 2005 and
the latter all fuel loaded after that date. The his<strong>to</strong>ric AGR fuel is the property of
British Energy and about three quarters of it is contracted for reprocessing
through THORP with the rest contracted <strong>to</strong> the NDA <strong>to</strong> s<strong>to</strong>re or reprocess at their
discretion. The new AGR fuel, including any arising from extensions of AGR
lifetimes, is contracted <strong>to</strong> the NDA <strong>to</strong> manage as they see fit.
A.24 For economic reasons, it is unlikely that THORP will continue operation beyond
its baseload reprocessing (due by 2015) and it is predicted that between 5,500
(Defra/NDA, 2008b) and 7,000 (CoRWM doc. 2520) tHM of AGR spent fuel will
remain in s<strong>to</strong>rage at Sellafield. The current plan for AGR spent fuel is essentially
for it <strong>to</strong> remain in pond s<strong>to</strong>rage. Apart from capacity issues, this is not a
satisfac<strong>to</strong>ry long-term strategy and it is incumbent upon the NDA <strong>to</strong> develop an
alternative.
A.25 AGR spent fuel is s<strong>to</strong>red in ponds at Sellafield. Some of it is in the THORP
Receipt and S<strong>to</strong>rage pond alongside (overseas owned) light water reac<strong>to</strong>r (LWR)
spent fuel and a large number of empty multi-element bottles. The pond water
chemistry cannot be kept sufficiently alkaline <strong>to</strong> prevent corrosion of the steel
cladding on the AGR fuel and there is a risk of leakage in<strong>to</strong> the pond water.
Sellafield Ltd has introduced short-term measures <strong>to</strong> manage the situation,
including the prioritisation of reprocessing for corroded AGR fuel (CoRWM docs.
2386, 2520) and work is in progress <strong>to</strong> find a longer-term solution.
A.26 In response <strong>to</strong> the regula<strong>to</strong>rs, the NDA is developing an “oxide fuels strategy”
(NDA, <strong>2009</strong>d; CoRWM docs. 2418, 2520, 2624) in which it will set targets for how
much of the remaining AGR fuel will be reprocessed and how and where the rest
will be s<strong>to</strong>red. The baseline plan is wet s<strong>to</strong>rage pending conditioning for disposal,
with dry s<strong>to</strong>rage being looked at as an option. However, this would require drying
of the fuel which has been s<strong>to</strong>red under water. As with Magnox spent fuel, no
CoRWM Document 2543, Oc<strong>to</strong>ber <strong>2009</strong> Page 104 of 151