Page County Sheriff Lyle Palmer reports his deputies were called Thursday to investigate the circumstances surrounding the death of a man found in a vehicle.  Deputies responded to 1851 A Avenue at approxiamtely7:30 AM. Following an investigation, which involved the Page County Medical Examiner and the Page County Sheriff’s Office, it was determined that 59-year old George Henry Mier, of Ottumwa,  had died from natural causes in a Semi tractor waiting in line to get into the business of Hallet Materials.  The Semi was parked on A Avenue facing north just south of the entrance to the business.