The Fond du Lac County Sheriff’s Office says speed and alcohol appear to be factors in a one vehicle rollover crash that seriously injured the driver. Shortly before 7:30pm Saturday night rescue personnel were called to the scene on CTH W and Kiel Road in the town of Calumet. An investigation showed driver and lone occupant, 25 year old Asael Gomez-Damaso from Johnsburg was traveling south on CTH W, when he lost control of his vehicle, striking a mailbox, entered the ditch, and the vehicle began to overturn. The driver was not wearing his seatbelt and was ejected from the vehicle. He was flown to Theda Medical Center with serious, but non-life threatening injuries.