10/25/2016 19:20 EDT | Updated 10/26/2017 01:12 EDT

Highway closed after rock slide injures contractors working to prevent slides

FIELD, B.C. — Two workers have been injured in a rock slide in Yoho National Park that has closed the Trans-Canada Highway for an extended period.

RCMP say the slide happened Monday west of Field, B.C., and that traffic has been stopped in both directions.

Parks Canada says in a news release the slide occurred at a rock scaling site, a process that industry websites describe as the removal of loose rock from a slope.

It says the workers were drilling holes to place explosives when the slide occurred.

The release says 10,000 cubic metres of rock and debris fell, and that a geotechnical assessment was underway Tuesday to make sure it would be safe for workers to clear the roadway.

Parks Canada says the two injured workers were both transported to hospital with non-life-threatening injuries.

"Parks Canada's thoughts are with the individuals and we wish them a speedy recovery," the release stated.

A photo of the slide shows two pieces of loading equipment among the debris — the one in the foreground appeared visibly mangled.

Parks Canada spokeswoman Lindsay McPherson said in an email that both pieces of equipment were involved in the slide, but she didn't know whether the injured workers were in them when it happened.

RCMP said in a news release Tuesday the closure could last up to 72 hours.

Police were suggesting a southern detour through Kootenay National Park, which could add several hours to a trip.

"It's expected to take a long time to clean up," RCMP Cpl. Curtis Peters said on Tuesday evening.

McPherson said the scaling work was being done to "mitigate unplanned rockfall events" and noted there was some irony that the slide happened during work to prevent a slide from happening.

The exact cause of the slide is still under the investigation.

Parks Canada said a update on the duration of the highway closure is expected to come Wednesday at 10 a.m. MT and will be posted to the Drive BC website.

Earlier this month, the Yellowhead Highway running through Jasper National Park was temporarily closed due to a rock slide west of the town of Jasper.

Police said some motorists suffered minor injuries when one vehicle that was attempting to avoid the rocks crashed head-on with another vehicle going the other way.