He graduated in 1970 from Alaska Methodist University with a B.A. in chemistry. He attended the University of Idaho graduate school on a fellowship studying organic chemistry. Sean then served several years as an Army officer with Nike Hercules missiles and later worked for the Army as test engineer on several laser and missile systems. An avid boater, he has been a Coast Guard Auxiliary volunteer in search and rescue, vessel safety, and safety education for more than 25 years. He currently works for the federal government as a chief of administrative services.