BOISE - Two construction workers died Tuesday after they were buried in a trench near Hill Road Parkway and Gary Lane, Boise Fire Department Battalion Chief David Cooper said.
The men were identified by the Ada County Coroner's Office as 26-year-old Ernesto Saucedo-Zapata of Nampa and 36-year-old Bert A. Smith Jr. of Caldwell.
The coroner says the men died of mechanical asphyxia due to compression, and ruled the deaths an accident.
Cooper said the three workers were working in a trench about nine feet deep that they had dug for a utility line when a wall collapsed on them just before 6 p.m.
Cooper told KTVB when Boise Fire crews arrived, they found one man partially uncovered in the trench and were able to pull him out.
He was transported by ground ambulance - still conscious - to a local hospital. His condition was unknown late Tuesday.
The bodies of Smith and Saucedo-Zapata were recovered from the trench before 10 p.m. Tuesday night.
"We spent the next three-and-a-half hours shoring up the trench, putting in boards on either side to prevent a secondary collapse while we were able to excavate the last two victims," Cooper said.
Cooper said Boise Fire has a specialized crew that has spent hundreds of hours training for trench accidents and other technical rescues. Still, it was imperative the crew took precautions for their own safety, he said.
"Once we go into a recovery operation, we tend to slow things down, and make sure we cover all ourt bases before we put our own crews into the trench," he said. "Once a trench has collapsed, there's a high likelihood that it's going to collapse again, so we want to take every precaution."
Firefighters cannot use heavy equipment to excavate the trench, because the vibrations could cause it to collapse again, meaning the dirt had to be removed by hand, using five-gallon buckets.
The heat and lack of ventilation in the trench, as well as the mental toll made for difficult work for the crew members. Cooper said members of the recovery team were rotated frequently to stave off exhaustion.
"You just feel for the victims, you feel for the families, and it's going through the minds of the rescuers the whole time," he said.
Roads were closed in the area as crews worked, but had been reopened by Wednesday morning.
OSHA is investigating the incident. The cause of the trench collapse is unknown.