Excessive speed, carelessness and recklessness were named as the main factors in a Georgia Department of Natural Resources report detailing the cause of a fatal high-performance boat accident on Lake Lanier in July that claimed the lives of two married couples. The DNR categorized the July 15 single-boat crash as a capsizing. It took the lives of the boat’s operator, Arthur J. McMahan, 46, his wife, Melissa Renee McMahan, 45, and two passengers, Anthony J. and Tammy R. Reece, 45 and 44, respectively.