Experts are working around the clock to try to stop toxic water from flooding out of a disused mine near Truro - its feared it could end up in the Fal Estuary. Pumps are working at full capacity at Wheal Jane, but levels are still rising.
If they can't get the situation under control, then there's the very real threat that polluted water will enter the nearby Carnon River and there'll be a repeat of a major incident in 1992 which polluted the Estuary.
Steve Hardy reports:
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Only handful of beaches have RNLI lifeguard cover during school holidays - the Maritime and Coastguard Agency warns.
Our Devon correspondent Seth Conway has been talking to a family who say without the hospitals, their children may not have survived.
It's going to be a windy one tonight and into the weekend - it could even touch gale force along the south coast.