Today's scenario is an incident involving the transportation of radioactive materials.
"It's extremely unlikely that an event like this could happen for real" said a spokesman for Magnox.
"However we can't allow ourselves to be complacent and need to be prepare for such eventualities".
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Occasional blustery showers overnight and brisk north-westerly winds. Patchy rain will continue during the day tomorrow.
Dame Shirley Bassey releases her first festive recording "The Christmas Song" with Brit-Award winning harmonisers Blake.
Private Gavin Williams was initially treated for a psychiatric episode rather than heatstroke an inquest hears.