They mentioned grout! No mention yet of pumping, but they do say they'll blast their way down. I hope somebody follows up on that, since buying tons of grout does have an environmental impact. You just have to look at that cement plant on the 401 by Bowmanville. Doesn't it have the most beautiful plume? It burns coal.
PS I'm only mentioning the blasting because it is impossible to pre-grout the shaft area, and then blast through. The blasting loosens the grout and the water comes in.