Ministry of Environment and Climate Change said that cleaning up the massive oil spill in the Grand River may take a month or longer.

A potential source of the spill was identified after a towing company near Kitchener reported an oil spill to the ministry’s Spills Action Centre.

About half of an 800-litre storage tank of used motor oil spilled inside the company’s facility and entered floor drains – explaining the direct impact to the storm sewer system that runs into the Grand River.

The name of the company that reported the spill has not yet been released.