Detailed design and engineering services at an existing power plant to perform structural dynamics and vibration analysis for an existing 4000-hp flue gas induced draft fan. This analysis was requested by the owner to investigate an ongoing balancing issue on the fan, which was causing frequent downtime for maintenance, repairs, and re-balancing of the fan. The scope of services included modeling the existing equipment, concrete superstructure, and foundations with finite element analysis software and comparing the response to industry standards and on-site measurements to identify areas of concerns and recommend the path forward. The existing foundation was determined to be close to the natural harmonic of the equipment, leading to resonance (excess vibration and displacement). A reinforced foundation with additional driven piles and mass concrete piers was designed to mitigate the issue.