Husky Energy said around half of the oil leaked from a spill last month has so far been recovered.
The company said there is no immediate deadline for when the clean-up will be concluded.
More than 1,570 barrels of heavy oil and diluent leaked from its Saskatchewan Gathering System pipeline on July 21st.
The spill has threatened the drinking water of riverside communities, according to officials.
Municipalities including the cities of Prince Albert and North Battleford have stopped drawing drinking water from the river, and using other sources temporarily.