The train that derailed in Saskatchewan last week spilled 1.2 million litres of oil.
After the train derailed, 85 residents were evacuated from the community of Guernsey.
Several of the train cars caught on fire.
The provincial government said that CP Rail will be responsible for all costs.
The rail line was reopened on Friday. The cleanup effort is expected to last several months.
As a result of the derailment, the federal government has ordered trains carrying dangerous goods to travel at a lower speed.