Manitoba's annual public accounts report says it could cost as much as 62 million dollars to clean up abandoned mine sites at Lynn Lake and near Leaf Rapids.
The report says water-treatment plants will have to operate for the next 24 years to clean up the contamination.
Mines and other developments across the province have left a trail of contaminants in their wake as their life span ends and only waste and byproducts remain behind.
M-K-O Grand Chief Sheila North Wilson says Indigenous people are still suffering the effects of the Sherridon mine, located 100 kilometres from Flin Flon.
It was closed down in 1951 but she says people in the area are still leery of eating fish and game.