Letter: Letters: Exposed elements

From DOUG McROBERTS

I feel that three points should be made about your article ‘Fire danger
at North Wales nuclear store’ (This Week, 2 March). Firstly, while a very
few Magnox fuel elements have corroded to the extent that uranium has been
exposed, it is highly unlikely that uranium hydride has formed in an air
atmosphere. Surveillance confirms that the affected elements are all dry,
stable and safe. The fire risk is therefore minimal; even if it occurred,
the design of the store-which is kept at lower than atmospheric pressure
with a full filter system-ensures that there would be no external risk.

Second, the problem was always localised. Only 46 elements out of a
total of 21 437 are affected, and of these, less than a third have exposed
uranium. Monitored radioactivity levels remain very low.

And finally, the design of the Wylfa store is not the base for any possible
future dry store for fuel from advanced gas-cooled and pressurised water
reactors. Apart from the fact that these later reactors do not have corrosion-prone
cladding (it’s stainless steel or zirconium), the designs we are looking
at incorporate sealed containers for the fuel elements.

We are now developing a method of safely removing the affected fuel
for reprocessing. It will, of course, be thoroughly vetted by the Nuclear
Installations Inspectorate.

Doug McRoberts Nuclear Electric plc Gloucester