As the search continues for two workers believed to be trapped in a Quebec quarry following a landslide, the man who managed to escape said Wednesday he’s thankful to be alive.

Benoit Robert addressed reporters at a hospital where he’s being treated for frostbite and minor injuries, thanking the rescue workers who pulled him out of the caved-in gravel pit on Tuesday.

The wall of the quarry in L’Epiphanie, about 50 kilometres north of Montreal, collapsed Tuesday morning, pulling in an excavator and two loading trucks that were on the site into the 100-metre-deep pit.

When the ground started moving below him, 47-year-old Robert said he thought he was having vision problems, but quickly realized what was happening.

A female co-worker who was in a nearby truck yelled: “We're sliding. We're going to die!” he said.

She and another male worker, both believed to be in their 40s, have been missing ever since.

Robert said he continued swinging the mechanical shovel he was operating back and forth in an effort to keep the excavator stable. He eventually got out of the vehicle and waited until a provincial police helicopter lowered a rescuer to pull him to safety.

"It's hard, what I went through. But I'm still here," Robert said.

The search for Robert’s co-workers resumed Wednesday morning, when a crane was brought to the site to transport heavy equipment into the pit to dig through the mixture of mud, clay and gravel.

At one point on Wednesday, 25 people were lowered to the bottom of the quarry, including a geologist.

Metal detectors, dogs and thermal equipment are also being used in the search.

Family members of the missing workers gathered on the site, waiting for news and meeting with search-and-rescue officials. Some politicians, including Quebec’s Minister of Public Security Stephane Bergeron, also came to meet with the families. 

“They are under a big anguish right now,” Bergeron said.

Authorities said the search will continue into the night. 

Police spokesperson Bruno Marier told CTV News Channel that it’s possible the workers managed to jump out of their vehicles before the landslide struck.

“We accessed one of the trucks (Tuesday) and no one was inside. Maybe they had time to jump out of truck,” he said.

“Since the second truck is covered with mud, we were unable to access it yesterday so that’s why, with the equipment, we’re hoping to remove the mud and get access to the second struck and maybe find a survivor in there.”

He said rescuers will proceed with extreme caution as the terrain surrounding the quarry remains unstable.

“They’re going to have to work with people watching at all times and some kind of a system with a siren,” Marier said. “If the siren goes off, everyone has a safety area where they’re supposed to be going to make sure that the work is done without jeopardizing other people’s lives.”

Efforts to reach the two missing employees were called off late into the night Tuesday on the advice of a specialist at the scene, as rescue crews couldn’t clearly see the shifting ground beneath them.

A layer of clay covers the rock in the area, according to a geologist, who said the excavation work may have put too much pressure on the soil, triggering the landslide.

The gravel pit is operated by Maskimo Construction Inc.

With a report from CTV Montreal