Ontario invests millions to rehabilitate former mine sites

The Ontario government will spend $5 million this year to rehabilitate former mine sites and restore some of their productive use. The initiative is part a 4-year, $27-million program launched by the Ontario government a year ago.

Mines Minister Tim Hudak made the recent announcement during a news conference at the former Coldstream copper mine, west of Thunder Bay.

“Improvements made at the Coldstream mine site demonstrate the benefits of our investment,” he told reporters. “The rehabilitation work we have done here clearly shows how this program can restore an important part of our natural heritage for the use and enjoyment of our children and future generations.”

Some 37 sites were rehabilitated during the first year of the program, including the abandoned Kam-Kotia copper-zinc mine, near Timmins.

The Kam-Kotia clean-up was among the largest projects to date. It was viewed as a priority because oxidation of the sulphide tailings and waste rock had created an acidic runoff that was making its way into nearby creeks and rivers. Ministry staff have monitored the mine site since 1991 to ensure that the runoff does not affect drinking water.

The clean-up was a joint effort among several ministries, including natural resources, the environment and northern development and mines.

Mining on the property began in the 1940s, as part of the war effort. Kam-Kotia Mines installed a 900-ton-per-day mill on the property in 1961, and by 1968 it was expanded to handle 2,600 tons. Operations ceased in 1972 after the company went bankrupt, at which point ownership reverted to the Crown.

Some mines in the rehabilitation program are even older, with several having operated in the early 1900s, when environmental standards were not in place.

The government now requires that each private company that begins either advanced exploration or mine production have a closure plan to restore land to a pre-mining state once operations have ceased. The closure plan must include the elimination of surface structures, underground stability assessments, re-vegetation, and physical and chemical stability assessments for tailings.

The government cited the Renabie gold mine, northwest of Wawa, as an example of successful reclamation by a private-sector company. After mining stopped, in 1991, surface facilities were demolished and 40,000 trees were planted. Grasses and shrubs now cover the tailings, and surface water meets provincial quality standards.

The government program also provides safety benefits, as old pits, deep trenches, open stopes and shallow shafts can pose hazards to children and outdoor recreationists. To prevent accidents, many old sites are backfilled and capped by a concrete cover.