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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Patchy rain and drizzle will continue this evening and overnight. Winds will remain brisk with temperature staying on the mild side.
With Christmas around the corner, we'd like to see your pets getting in the spirit in their festive outfits.
ITV News has spoken to one social worker who says the system is unsafe, blighted by bullying and high case loads.