LEADVILLE, Colo. (KDVR) — In a historic mining town like Leadville, there’s no telling what’s just beneath your feet.

However, it’s not all gold and silver.

In fact, one man is lucky to be alive after stumbling upon a giant sinkhole last Thursday outside of a storage complex.

Authorities say the man was walking to his storage unit when all of a sudden the asphalt underneath him gave way and he fell 30 to 40 feet into the sinkhole, landing in a big pool of water and ice.

A family witnessed it happening and called 911.

Leadville firefighter Alex Conlin was among the first rescuers on scene.

“The bottom was just a lake of water. There were chunks of ice flowing everywhere,” he said.

Conlin quickly geared up and began rappelling from a fire ladder into the 15-by-15 foot sinkhole. Not only were the sides of the pit unstable, the water at the bottom was deeper than he imagined.

“The water was up to my chest on me, but I hadn’t reached the bottom because I was holding onto a rope to keep me out of the water, but there was no bottom to be found,” Conlin said.

Somehow the injured man in the pit had managed to pull himself onto a small shelf.

“It was less than a foot big, eight or 10 inches, sloped and muddy,” explained Conlin.

That left Alex little room to work. He repeatedly slipped and fell while trying to attach the man to ropes.

Both men were cold and fending off hypothermia when they were lifted to safety about 90 minutes later.

“When I came out of that hole I was very excited to not be there anymore and very excited to go into a warm ambulance,” Conlin said.

The victim has not yet been identified. He was flown to a Denver area hospital to be treated for his injuries.