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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National Trust Wales is celebrating 50 years of a campaign to protect and preserve more than 500 miles of coastline.
A poll by children's charity The NSPCC has found nearly one in ten 12-13 year-olds is worried that they are addicted to porn.
The Liberal Democrats will meet later today in Pentwyn for the launch of the party's general election manifesto.