The Florence County Sheriff's Office arrested Sam Miles, 53, Wednesday morning.
He's charged with Pointing and Presenting a Firearm at a Person.
On March 19, deputies say Miles showed up at his former job at the South Carolina Department of Transportation office on Highway 378 in Lake City.
They say he fired a shot in the air and left.
No one was hurt.
Deputies didn't release a motive in the shooting.
Miles is awaiting a bond hearing at the Florence County Detention Center.