The fire service worked through the night to assist with the pumping of toxic water from a disused mine near Truro.
Pumps are currently at full capacity at Wheal Jane. Levels are still rising, but at a slower rate than yesterday.
There are fears that rising levels could pollute the nearby river and Fal Estuary, a marine special area of conservation, although there has been no pollution so far.
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Sunshine all day tomorrow and warm week ahead
Lovely and warm with highs of 23 and 24 degrees. Hottest on Wednesday.
Searches are being carried out in Nunney in Somerset for 86-year-old Kenneth Scotcher.