David Mangan, age 52, of Fortuna, was operating a roller-compactor at a road construction site on Alderpoint Road, north of Cemetery Road, near Blocksburg.
For reasons still under investigation he allowed the piece of equipment to leave the east roadway edge. The roller traveled out of control down a descending embankment until it struck a group of trees, which caused the roller to come to an abrupt stop. Mangan was ejected from the roller and received major injuries.
He was flown to Mercy Hospital in Redding.