Regreening results look positive.

• Author: Ross, Ian
• Position: Paper mill sludge used to enhance growth of vegetation at former mine tailings site - Brief Article

Paper mill sludge used to enhance growth of vegetation at former mine tailings site

Mining and academic researchers are experimenting with wood sludge near Elliot Lake in bringing a former mine tailings site back to life. In closing up their Pronto Mine site at Spragge, Rio Algom Ltd. has been spreading paper mill sludge to determine if it provides an adequate capping material to re-green a copper tailings waste area.

Working in conjunction with Laurentian University, the Northern Ontario Mines and Mills Alliance (NOMMA) and St. Marys Pulp and Paper, the scientists and technologists observing the vegetation growth on a barren one-hectare test plot are encouraged enough by what's taken root to expand the program to five hectares and eventually clean up the whole site.

Rio Algom operated 16 mines sites in the Elliot Lake area, dumping millions of tons of copper and uranium tailings in a number of waste properties.

Providing some transportation issues can be addressed, Graeme Spiers, director of Laurentian's Centre for Environmental Monitoring says the process could be mutually beneficial down the road for both the mining and paper industries in finding new uses for waste material.

"Wood sludge is a relatively clean, benign material," Spiers says. "It doesn't have some of the bleaching chemicals used later in the (pulp and paper) process.

"It's sort of like putting a woody layer of compost on top."

During the winter of 1998-99, researchers spread a centimetre-layer of coarse limestone at Pronto to neutralize the high-acid runoff of dissolved metals. Next, a 50-centimetre layer of sludge was put down, then the whole area was hydroseeded.

The results were apparent within a few months.

"I've...