Deaths on Golden State Freeway Probed : Accidents: State labor official says improper bolt removal may have caused a wall to collapse in Arleta. Trucking incident is also investigated.

A construction accident on an Arleta freeway on-ramp that killed one man may have been caused by human error when workers broke from their routine and removed all of the bolts that held a 5,000-pound, quake-damaged sound wall in place, according to a state labor safety official.

Construction worker Brian Fourte, 24, of Los Angeles was killed Tuesday when one section of the sound wall collapsed, possibly because workers removed all the bolts that held it in place before attaching clamps from a crane that would have supported it, officials said.

Fourte was pronounced dead at the scene at the Branford Street on-ramp to the southbound Golden State Freeway, said Brian Humphrey, a Los Angeles Fire Department spokesman.

“It looks like it could have been prevented,” said Rick Rice, a spokesman for the California Occupational Safety and Health Administration.

“We will look to see if proper procedures were followed and if the (Rondeau Bay Construction Co. of Oakland) had a system in place to prevent this type of thing from happening.”

Alan Dones, president of Rondeau Bay, said company officials do not know what caused the accident and are conducting an investigation.

Meanwhile, California Highway Patrol officers are continuing an investigation into an accident on the same freeway, about three hours earlier, in which a Santa Clarita Valley man was killed by a 30-foot iron pipe that fell on his car.

Charles Fedorko, 46, was traveling north on the Golden State, near its intersection with the Foothill and Antelope Valley freeways, about 4:15 p.m. when a load of the pipes, each weighing about a ton, fell from a big-rig truck on a ramp above, police said. One of the pipes sheared off the roof of Fedorko’s car and killed him instantly.

How the pipes, bound to a flatbed trailer by nylon straps, came loose is still under investigation, said CHP Officer Wendy Moore.

CHP officials said a truck driver is normally responsible for securing his load, but they have not yet determined if charges will be sought.

The truck was owned by Westran Inc., a trucking company with offices in Vancouver, Wash. Westran officials declined to comment.

Fedorko lived in the Stevenson Ranch area, just west of the Santa Clarita city limits, with his 14-year-old son.

Times staff writer Chip Johnson contributed to this story.