Fire crews have contained a vegetation fire burning off Highway 1 south of Lompoc Thursday afternoon, according to the Santa Barbara County Fire Department.
Capt. David Sadecki said Thursday night that investigators determined the cause was related to a welding and cutting operation.
He said the blaze was reported at about 1:50 p.m. at 6773 Highway 1, one mile south of the highway near Rancho San Julian.
It was fully contained at 3:30 p.m. after burning 6 to 8 acres, Sadecki said.
The fire was burning in a canyon about a mile south of Highway 1, Sadecki said.
About 80 firefighters were dispatched to the incident, assisted by water-dropping helicopters, Sadecki said.
No injuries were reported and no structures were threatened, Sadecki said. Highway 1 remained open.
Cause of the fire remains under investigation, Sadecki said.