Paschal Solutions, Inc. (PSI) Share: Engineering Services Paschal Solutions, Inc. (PSI) Visit Website P.O. Box 71346 Knoxville, TN 37938 270-556-4864 About Map About PSI established in 2000 is a premier provider of nuclear safety and engineering services. PSI, is a Woman Owned Small Business delivers unique solutions for private industry and government. What's Nearby? Distance: 5 10 15 20 25 50 mi.