The cleanup continues following a train derailment that spilled a fuel product in the Fort Frances area.
A CN train went off the tracks Friday afternoon near Barwick leading to the evacuation of homes nearby.
The Ontario Ministry of the Environment said one of the derailed cars is estimated to have spilled up to about 45 thousand litres of petroleum distillates.
Ministry officials have been on site working with emergency responders, as well as workers from CN Rail.
On Saturday, the MOE said the spill was not expected to threaten surface waters, including the Rainy River.
Containment booms were put in place to keep the spill from spreading and a vacuum truck was on site to capture the liquid.
A statement from the provincial ministry said the transportation of dangerous goods, including oil, is the responsibility of the federal government.
"We have repeatedly called on them to do more to improve rail safety and regulations to better protect our citizens, communities and the environment," the statement said.