Charles was born September 25, 1937 in Jersey City, New Jersey to the late Thomas and Alice Kennedy McMahon. Charlie graduated Magna Cum Laude in chemistry from St. Peter's University with a commission as Second Lieutenant, US Army Reserve. He studied organic chemistry at Rutgers University and earned a Master's of Science. In 1976 he earned a Master of Science in Administration Management from Georgia College and State University. Charlie's long career with the Civil Service began with the Department of Defense Chemical Corp. He was then called to Georgia to work with the US Forest Service to study the effects of smoke and pollution on air quality. He then found his way to Columbus, Georgia where he was a project leader in the Longleaf Alliance, an initiative of Auburn University's Forestry Department. Retiring in 2004, Charlie was recognized by the US Department of Agriculture for his lifetime work. Charlie loved the outdoors and could fix anything he put his mind to. He was well traveled and always in the company of his wife Pat and their favorite travel companions Waggie (his sister) and her husband Tom. They visited nearly all parts of the world. Charlie passed away March 16, 2022 in Columbus, Georgia. He is survived by his wife of 57 years Patricia Kirchkesner McMahon, daughter Jennifer "Jenny" McMahon Miller, son, Thomas Charles McMahon, sister Margaret "Waggie" McMahon and brother-in-law Tom Muldowney.