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.
More top news
A light breeze winds across the region, with clouds and rainy spells. There may be mist or fog in places.
Tonight will see light winds across the region, accompanied by cloudy skies, outbreaks of rain and mist and fog spreading north overnight.
Campaigners fighting the abuse chose Bristol bus station to try to educate the public on a growing problem.