The CBC has a detailed report on cleanup and remediation efforts along the NWT section of the old Canol Road.
https://www.cbc.ca/news/canada/north/canol-trail-cleanup-1.6527710
QuoteThe federal government wrapped up its remediation of the Canol Trail – an abandoned, World War II-era road through the Mackenzie Mountains – in 2019, but a co-founder of a yearly hike along the route isn't pleased with the amount of debris that remains there.
... Work related to the Canol Trail cleanup had been underway for more than a decade before the remediation began in earnest in 2018. That work involved environmental assessments, elder interviews and the formation of a working group.
... Ron Breadmore, an acting senior manager at Crown Indigenous Relations and Northern Affairs, said in an emailed statement that there were a number of reasons why the trail wasn't cleared of all traces of the CANOL project.
He said some stuff – like material from collapsed buildings, empty drums and old bridges – poses a low risk to human health and the environment.
Other things, like old vehicles and pump houses, are not dangerous for humans, wildlife or the land, said Breadmore. They're also relics of the trail's "historical legacy," and have "heritage value."