A man from Woodbury County was injured during a single-vehicle rollover accident Friday afternoon in Monona County. The Iowa State Patrol reports 58-year old Mark D. Wolterman, of Danbury, was driving a 1995 GMC AERO, when his brakes apparently failed as he was traveling down a hill. as he was westbound on County Road L-32 The vehicle flew through a stop sign at the intersection with E-34 before rolling over onto the driver’s side into the intersection. Wolterman was transported by LifeNet to Mercy Hospital/Sioux City for treatment of unknown injuries.  The Patrol says he was wearing his seat belt.