Canadian Pacific Railway said its crews are still working diligently to clean up the estimated 1.5 million litres of crude oil that spilled from a derailed train on Dec. 9, and expects to be there for a number of weeks.
The spill resulted in a fire that burned for around 24 hours.
One University of Saskatchewan professor said remediation teams need to keep a number of things in mind as they clean up the area.
Steven Siciliano noted details about how fast oil was spilling out of tank cars could make a difference.
“If it’s slowly seeping, what happens is you can kind of imagine a sort of pancakes, so then it doesn’t go as deep. Whereas if it’s rapidly spilling, it can actually get deeper into the soil. And the deeper in the soil it gets, the harder and harder it can get to remediate,” said the soil science professor.
He added the Prairies have glacial till soil, which means it is made up of large clay layers which make it hard for water and air to go through them and making clearing oil very difficult.
Siciliano added many regions don’t have soil that freezes, which means techniques used in other areas won’t be as successful at the derailment site.
He said many technologies have been developed in places like Oklahoma, California and southern Ontario, but the soil in Western Canada is much different from those places.
The professor added this is one of the largest oil spills in Saskatchewan’s recent history.
The Husky oil spill in July 2016 — where approximately 225,000 litres of oil spilled into the North Saskatchewan River — is equivalent to a little more than 1,400 barrels of oil.
Last week’s spill near Guernsey was more than six times larger, with 9,400 barrels of crude spilling due to the derailment.
The Transportation Safety Board’s preliminary report found 19 of 34 cars that derailed lost entire loads.