Imperial Oil is still investigating whether produced water that spilled at the Norman Wells, N.W.T. operation in late July has entered the Mackenzie River.
A spokesperson for Imperial Oil said in an email that the company is monitoring the water quality and there are no indications there is a risk to public health.
This comes after people downriver in Fort Good Hope reported surface contaminants on the water.
August is a busy time for fishing along the Mackenzie River in Fort Good Hope, Edwin Erutse, president of the Yamoga Land Corporation, said in a previous interview with CBC News.
The Imperial Oil spokesperson said from Aug. 10 to 12 an external environmental consultant collected water quality samples along the Mackenzie River, beginning near Goose Island and continuing at 20 km intervals. This covered 100 kms of the river in total.
Other samples were collected at Fort Good Hope with Guardian representatives present through the K'ahsho Got'ine Foundation, the management arm for the new Indigenous and territorial protected and conserved area.
The spokesperson didn't say what the results were from these samples.
The spill was reported to the N.W.T. Department of Environment and Natural Resources on July 27 and according to the federal regulator occurred between Bear and Goose Island.
Produced water is treated water that is pumped to the surface during oil recovery and then reused. According to Transport Canada, produced water can contain contaminants from oil extraction, but it varies with how much it contains.
The company estimates the quantity of the spill is 55 cubic metres (55,000 litres).