Investigators are looking into how a construction worker fell into a 15-foot muddy trench in Falls Church, where he was trapped for about eight hours before rescuers were able to free him.

The man was transported to an area hospital for what rescuers said were life-threatening injuries, although they did not release more details of his injuries.

About 4 p.m. Thursday, the man was working at a home in the 7400 block of Venice Street to install a sewer line when he fell into a recently dug trench.

Rescuers said the heavy rainfall over the past few days made more dirt wash into the trench area, and when the man fell in, he was in a “mud bog and couldn’t move,” according to Dan Schmidt, a Fairfax County fire department spokesman.

“He sunk down to waist level and was unable to get out,” Schmidt said. “What made it so difficult is the dirt inside was basically mud. You just can’t get out of something like that.”

Rescue of man in 15 foot mud hole. (Fairfax County Fire Department)

It took roughly 100 rescuers from fire departments in Fairfax and Arlington counties eight hours to get the man out of the muddy trench.

Schmidt said paramedics had to be “very careful” that the man didn’t get hurt as they used a backhoe and other heavy equipment to try to extradite him. The man remained conscious the entire time, he said, but did lose circulation around his waist and legs.

Officials from OSHA are expected to investigate the incident, according to Fairfax fire officials.

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